well - that's a new one!? ya just can't make this stuff up.
is it authentic? we could speculate but we'd have to be IN his head....and that's not a good place. it does seem rather SUDDEN, like in the last week?? a person who is struggling with gender identity had done so for a long long long time, and this is probably best explored with a qualified therapist. but it doesn't usually wait until later in life to express.....one may "hide" their sexual preference but a true gender identity 'crisis/conflict' would have expressed itself in some ways. it would not have gone unnoticed.
so why would someone "pretend" to be cross gender? you'd have to be pretty scrambled eggs mentally........i'm thinking drugs, like meth or crack. when i was on crack, my mind went to a LOT of strange places. sick, twisted, sexual based stuff. so i know the mind can go to some dark or just plain freaky places.
i'm sorry for your kiddo. if it were TRUE that her father is having a true gender identity shift or change, that's tough enough for a child, but is manageable. but if this is just one display of a truly defective person, she really has no "process" to grab on to.
let's see where this is in a week or a month.
don't put any of this on YOU. like you should have known. you aren't dealing with a normal person, but a very messed up person.