Since the vast majority of these lines are disrespectful to other demographics in addition to the trans population, I'll also attempt to summarize the broader categories of folk who are likely to be insulted by the same wording in order to emphasize that it really would be more intelligent to avoid these lines completely rather than just being careful who you say them to.
"Don't worry, I'm sure it's a phase you'll grow out of."
How long do you suppose this 'phase' takes to grow out of? After how much waiting is it reasonable to conclude that it wasn't 'just a phase' and that the permanent reality now needs to be acknowledged? That's a line that is somewhat reasonable to use with a child, but utterly insulting to use on an adult. Telling an adult that you expect them to 'grow out of' a transitional 'phase' is essentially saying that they're immature and that you know them better than they know themselves. Again, that might be true with a child, but is a ridiculous claim to make with a mentally competent adult.
Even worse, this line is typically used in complete disregard to just-expressed long-term duration of the situation... which demonstrates that you weren't listening at all to what you were just told. If you're dishing out illogical advice that clearly contradicts the information you were just given, do you really expect anyone to take you seriously? That's not the way it works, so please please please don't expect us to be respectful of your opinion when you're obviously talking nonsense.
Even if the subject of your commentary is a child, the wording above is still far from helpful. Children certainly do go through phases... but to assume that every characteristic they display will later disappear would be crazy. Children begin to show hints of their long-term personality at a very early age, long before they develop effective communication skills, so by the time a kid is old enough to articulate to you that they feel like they've got a brain-body mismatch it's not particularly likely that the condition is one they're going to outgrow. A misunderstanding/development that IS worth considering would be that a child or young adult may not yet have an adequate vocabulary to describe their experience... an example of this would be the fairly common scenario where a trans person who is sexually attracted to individuals of the same birth sex initially identifies themselves as homosexual because they're familiar with that term but not the terms transgender or transsexual, and later on in life after having been introduced to the additional categories realizes that trans is a more accurate category for them. When the person you're addressing is young (and/or has had limited communication with those of the same identity) enough that lack of established vocabulary could potentially be limiting their ability to fully express their identity, more reasonable and helpful alternative responses include "Ok, let's wait [specific duration of time] to see how your understanding of this develops" and/or "Let's do some research on people who are [title of identity in question] to see how your experiences compare with theirs."
Who else would find this comment offensive? Pretty much everybody that it gets use on, including those who experience non-heterosexual attractions, and those who are pursuing any other type of alternative lifestyle (from communal living to veganism/vegetarianism to childlessness-by-choice). This line is essentially a generic one-size-fits-all "I consider what you're doing/thinking to be selfish and immature, but I'm to polite to say that out loud."
"I don't think there's anything unusual about you at all. There's lots of..."
... men who like to cook.
... women who like sports.
... boys that play with dolls.
... girls that hate pink.
[... or any other trivial example of people stepping outside the established bounds of their assigned gender.]
Being trans isn't about having interests that are outside the arbitrary boundaries that our culture has drawn based on gender stereotypes; it's about one's core identity, who we are on the inside. This identity certainly gets expressed in various ways that might or might not tend towards the behaviors and interests that are typical of those with the cis-gendered version of our identity, but healthy well-rounded human beings do not define themselves (or others) based on a checklist of stereotypical behaviors or social roles. While it is appreciated that you're open-minded enough to not initiate derogatory name calling at the first sign of cross-gender behavior, denial of another individual's expressed identity really isn't all that much better. If you find one example of cross-gender interest/experience to be unconvincing (which is fine, variability in at least a few aspects is normal), try asking for more examples... and accept the overwhelming list that's likely to follow.
But don't let yourself get caught up in tallying up a list of cross-gender vs gender-conforming characteristics, because identity isn't about whether one's outward behavior and interests is closer to the male norm or the female one. It's about being (or not) comfortable living in a body that has a particular set of anatomy, and having permission (or not) to interact with other human beings in a manner that's consistent with one's inner identity. It's about looking in the mirror and seeing (or not) a reflected image that one recognizes as "me". No amount of tallying external expressions can quantify that internal experience of oneself.
The problem with these statements which recognize and validate deviation from the accepted behavioral binary, is that they are simultaneously reinforcing the stereotype that you are noting an acceptable deviation from; listing variations that are acceptable implies that there are other variations which are not so. If one has the attitude that a particular action or interest is genuinely a valid pursuit for all persons of any/all gender(s), one doesn't give stereotypes on that matter recognition at all. If cooking is a good skill for anyone to have, the commentary on a cook's gender/sex is unnecessarily drawing attention to an aspect of that person that is completely and impolitely irrelevant.
Case study example from my own life: I am a licensed engineer who happens to also have a female body, in a field of engineering that has an approximately 9:1 male-to-female ratio. My female presentation gets commented on A LOT... and while nobody has ever said anything blatantly derogatory about my role as a female engineer, I wince at every single one of those claim of admiration for my being a female engineer. Why? Because my sexual anatomy is not something that should be getting openly discussed with near-strangers that I happen to be encounter in a professional setting... and yet, all commentary on my apparent femaleness is a thinly veiled version of exactly that, a type of sexual harassment that is widely tolerated only because it isn't dished out with deliberate hostility. And while I'm probably more sensitive to commentary on my status as a female engineer than others with the same role due to my trans identity, I'm seriously doubt that cis-female engineers appreciate constant reminders of their minority status either.
Who else is harmed by this confusion of external expressions of cross-gender behavior/interests with gender identity? Everyone who has interests and/or skills that happen to fall outside their gender's box (which is normal... so essentially everyone). When score-keeping is happening on who is following the expected list of stereotypical behaviors to what degree (even if it's on a subconscious level), there's a strong incentive to adjust the frequency or publicity of the behaviors being tallied accordingly. Some people will express their displeasure with the system by deliberately breaking the social "rules", while most will quietly suppress and/or conceal aspects of themselves that are counting against them on that virtual scorecard. Both of these approaches deny the individual (and the community) the benefit of all God-given talents being fully developed and put to good use. The only way you're going to be able to really see someone as they are is to stop comparing them to the default set of stereotypes and start seeing them as a unique individual.
"So.. you're gay?"
or
"You're not trans, you're just gay."
Two unfortunately common expressions of the same fundamental misunderstanding, confusing sexual orientation/attraction with sexual identity. These are separate characteristics of individual human beings that would be recognized as completely independent of each other if we weren't so stuck on defining sexual attraction as relative to one's own sex. Our hetero-normative culture has defined "heterosexual" as "attraction to the opposite sex" and "homosexual" as "attraction to the same sex" (with use of the terms "sex" and "gender" interchangeably)... which works just fine until you start trying to apply these labels to someone whose gender identity doesn't match their sex (or used to not match, but does now thanks to having received gender-conforming surgery).
Is a male-identified person with a female body who is attracted to female-bodied people a lesbian or a straight man? Obviously that's primarily a function of whether you recognize this person as a man or a woman, since there's no question of what category of people they find themselves attracted to. And the matter gets even more mucky if said individual sometimes presents themselves as male and sometimes presents themselves as female. Again, I want to emphasize that who this individual is attracted to is clear, but with the baseline reference that's necessary for the accepted terms for describing physical attraction ("heterosexual" and "homosexual") being somewhat ambiguous, both of those terms become not very helpful in communicating what they were intended to convey.
A good general rule for these situations would be to just avoid using hetero-normative terms (heterosexual, homosexual, gay, straight) completely... in addition to avoiding attempts to discuss aspects of someone else's private life that are really none of your business in the first place. Where references to a trans individual's sexuality are warranted (such as informing a mutual acquaintance why trying to set them up for a date with a particular other individual would/wouldn't be worth doing), wording such as "not attracted to men" gets the point across just fine without getting into the unnecessary private details. This wording also works well for truthful-but-not-outing references to non-binary sexual identities (bisexual, pansexual, asexual, etc).
If the trans individual initiates use of hetero-normative language sexuality terms in reference to themselves, it's fine to follow their example in application of those terms... but don't go trying to assign sexuality labels to them; if you're guessing, there's a high chance that you've got it offensively wrong.
"You are a daughter/son of God."
That statement is just fine when selected in agreement with the target's gender identity; when used in direct conflict with their identity, it's a blatant denial of that identity. You may have intended it as a reinforcement of belief in divine love for the individual, but when you use the wrong gender term with regards to a trans individual it conveys your belief (and a false claim that all other members agree with you) that one's birth sex is the end-all determinant of spirit gender.
Unless you've been given the Gift of Spiritual Gender Discernment, you have no business making claims that you know the true gender of any individual other than yourself. Nor do you have any business quoting "The Family: A Proclamation to the World" or any other extant Church scripture or statement in support of such a claim, because while those sources do establish that male and female spirits exist, there is no official doctrine on how to define the gender of each unique individual. Cases of spirit gender opposite one's sex assigned at birth have been recognized by the First Presidency for a few individuals, so the common claim that no such recognitions will ever happen has already been proven false.
That being said, you don't need to accept that any particular individual has a spirit gender contrary to their birth sex in order to maintain civility. It's fine to acknowledge that such information is not verifiable at this time, with faith that it will be made clear at some point in the future... and while gender neutral pronouns can be awkward for everyday language, this particular statement has a gender-neutral version already in circulation: "You are a child of God." With a simple substitution of just one word, all of the positive connotations you intended are retained while all of the negative connotations are discarded!
"Just keep the commandments."
There are two huge problems with this piece of advice:
1) The direction to "keep the commandments" implies that your target audience is not currently doing so. This is insulting to those who actually are, particularly when accompanied by other statements that imply suspicion of specific commandment violations (the Law of Chastity is the one I most often hear mentioned in the same breath). Opening up to discussion of something as misunderstood as the trans experience is difficult enough already, don't make it worse by tossing in false accusations!
2) The suggestion to "just keep the commandments" puts responsibility (i.e. blame) on the individual receiving said advice. Any improvement in the situation is assumed to be the result of the individuals faithful devotions, and lack thereof is assumed to be simply said individual not trying hard enough. This emphasis on spiritual responsibilities actively discourages the individual from seeking help and support (such as from professionals with applicable credentials or peers with similar experiences) or more understanding in relationships with those who have been making hurtful statements/claims (such as family members and local Church leaders).
While keeping the commandments is certainly an exercise worthy of more attention from all of us imperfect mortals, it's not a particularly good blanket-fix for problems that are largely outside the individual's scope of control. Would you give this advice to a woman needing safety from an abusive husband? A father struggling to find employment adequate for support of his family? A young single adult fighting crippling depression? Not preceded by a "just..."! Like any other complex situation, supporting a trans individual requires asking enough questions to gain some basic understanding of what the problems being faced are and then referring to appropriate resources. Doing that first, and then following it with "and continue striving to keep the commandments" would be much more appropriate!
"Don't you want children?"
or the less-often-heard versions that the above question is the "polite" edit of:
"But I want grandchildren!"
"You're not going to reproduce? Don't you see how happy I am centering my life around my children? How selfish of you!"
First off, let's review what Church policy on child production is:
The decision as to how many children to have and when to have them is extremely intimate and private and should be left between the couple and the Lord. Church members should not judge one another in this matter. (Handbook 2, 21.4.4)Yep, that "more is always better" stereotype and the labeling of those who don't pop out a minivan full as "selfish" are cultural relics that are in direct conflict with current direction from those we sustain as prophets, seers, and revelators.
Second, let's look at what the motivations behind these statements are...
The would-be-grandparent is more concerned for their own comfort and enjoyment than that of their offspring, the target of their complaint. They have set an expectation that somebody else will take on the struggles and responsibilities necessary for them to enjoy what they have defined to be the proper retirement life, rather than taking action on their own to ensure that goal is met.
The similarly aged parent is projecting their own experience and motivations, assuming that the target of their remarks has the same level of opportunity (both in partnership and ability to tolerate the process of creating children) as they do. They see their own approach to family life as the only one worthy of consideration, and are reinforcing this belief by looking down their nose at all others.
Neither of these commentators has paused to consider what reasons the target of their criticisms might have for not reproducing; it is assumed that child-production is a relatively simple matter for all, and that every parent will find the process to be enjoyable far in excess of the pain and challenges involved. They have leveled an accusation of selfishness at the target without bothering to check whether or not the facts of the case would support such a conclusion, and in their own motivations for doing so they are guilty of the very sin they seek to convict the other of.
Third, it important to note that reproduction is not the same as parenthood. There are individuals who produce children who will be parented by someone else, either by conscious planning or by contested removal of children from an unhealthy home situation. There are parents who devote themselves to children they had no part in the production of, by accepting a step-child as their own or by adopting/fostering children from unconnected families. While there are certainly people who choose to not reproduce because they do not want to be parents, to assume that this is the only reason one would not personally reproduce is a gross insult to those who do not have an opportunity to produce natural offspring (whether it be due to lack of a suitable partner, fertility challenges, or other health issues) as well as every member of families that were created by other means.
How much irreversible body change from natal hormones is a worthwhile price to trade for the privilege of natural reproduction? How much time is it worth spending in the local psych ward (as opposed to being just fine while on gender-congruent hormones)? How high of a death-by-suicide risk is reasonable? Those are the factors we get to evaluate, on top of the “normal” pregnancy and newborn-baby discomforts. We're happy that your choice to reproduce was right for you, but that assumption that the benefits always outweigh the costs really needs to stop.
