Nothing is confirmed except for one, the oldest. It seems she has at least exposed the other two to gender ideology.
Daily Mail article from last year: https://archive.is/QOCjq

She told [Glamour] magazine: 'I bought a bunch of books that sort of addressed these things and addressed a full spectrum of what this is.
'Some of the books are written by transgender children. Some of the books are just about how you can be a boy and wear a dress; you can express yourself through your clothing however you want. And that doesn't even have to have anything to do with your sexuality.
'So from the time they were very young, I've incorporated those things into their daily lives so that nobody feels like they are weird or strange or different.'