when our younger kid transitioned, the resources on social transition that I found emphasized that it's important for the child's mental health that they know that they can change their name/pronouns again (or back!) at any time and that their parents will continue being supportive.

and indeed, our kid went from nonbinary (they/them) to boy (he/him) and back to nonbinary (they/them) after sticking with boy for a few months.

it wasn't that hard to just go with it and make them feel like we weren't going to freak out at any stage.

LW is doing something that increases the risk of suicidality in their child and I wonder if they know that. Because I would absolutely not be doing that to my kid, I tell you what.