Ever thought about a gender reassignment where you substitued male for female characteristics or the opposite?
I haven't for myself, but I know people who have been in that situation.  I'm all for it.
Did your friend do hormone therapy?
He did, yeah.  Still going through it.  He was born a biological female, and for the longest time thought he was just a lesbian.  But something wasn't quite right still.  Admirable person.
Has there been surgery to modify some characteristics?
Not yet.  Not sure what he's considering, and it's kind of private, so I haven't asked.  What do you know about the subject?
Sex change
Sex change is a process by which a person or animal changes sex – that is, by which female sexual characteristics are substituted for male ones or vice versa. Sex change may occur naturally, as in the case of the sequential hermaphroditism observed in some species. Most commonly, however, the term is used for sex reassignment therapy, including sex reassignment surgery, carried out on humans. It is also sometimes used for the medical procedures applied to intersex people. The term may also be applied to the broader
people born with physical sex characteristics "that do not fit typical binary notions of male or female bodies". The opposite of "transgender" is "cisgender", which describes persons whose gender identity or expression matches their assigned sex.
The degree to which individuals feel genuine, authentic, and comfortable within their external appearance and accept their genuine identity has been called "transgender congruence". Many transgender people experience gender dysphoria, and some seek medical treatments such as hormone replacement therapy, sex reassignment surgery, or psychotherapy.