My daughter (12) told me a couple of days ago that "gender is how you feel inside". School had told her 
I asked her what gender she feels like inside and she just looked at me. So I asked if she understood the question or how to answer it. She said "not really".
So we talked about gender stereotypes and how you might be able to tell A Girl and she nodded to some and turned her nose up at others.
Then we talked about how you might be able to tell A Boy. She laughed and agreed with some of the things - loud; have smelly toilets at school; have short hair (although she objected to that as some of her male friends/brother have long hair) and then I went on to describe other 'boy' things and she just said really quietly "but I like some of those things..."
Oh. Yes of course you do. Are you a boy? (No) So are those really 'boy' things then? (No)
And then we thought of her friends and the ways in which they do/don't fit the stereotypes (spoiler: most of them don't...)
And then she signed the petition.
I did have to steer her away from going to school and re educating everyone though. Which bothers me, but I can't afford for her to get into trouble at achool.
Sir, my daughter also asked if we could move the country.
She asked what self I D would mean and I just explained really calmly (I don't want to scare her!) and she said "but that means evil men could go into the girls toilets and just say they are girls" and "but boys are stronger than girls. Won't they win all the sports?" and "why can't boys and girls just like what they like?"