At What Age Do Children Start to Realise they are Gay?

We could equally ask when do kids start to think they might be heterosexual?
An assumption of heterosexuality  is dominant in our society.
It is assumed we are all straight and our children will be straight.

The fact is that between 9 to 12 years of age is typically when children start to develop interests in the opposite sex or have same-sex desires, though for some it will be later.

Personally I have known many lesbian and gay teenagers so for me these aren't fanciful made up statistics.  When books, films and TV for children only show opposite sex couples they are making like harder for children who are different.

Parents may find this article interesting: http://www.parenting.com/article/could-your-child-be-gay

All kids should read books with gay characters, like Nico Di Angelo, which would make an easier transition from child to teenager, to adult.