Charming as usual ; )
There is no proof that they are "born that way". And believe me they have looked for it. It is the holy grail of politicized science along with embryonic stem cells being the universal cure all for everything from hair loss to death.
Both of those things have turned out to be complete duds no matter how much money they pour into it.
But when you search for nurture related reason for people become homosexual they are all over the place. I just go with the preponderance of the evidence.