Normally, asking someone who is transgender about their “parts,” or what operations they’ve had is VERY inappropriate, in case any of you are wondering.
If you are curious to learn more about what being “transgender” is about, there are plenty of books. I think “The Transgender Child” is a decent place to start. PFLAG has a more comprehensive list if you are looking for a more nuanced selection.
Oh, and any negative/doubting/joking comments about anything to do with transgender issues will be deleted.