Re: "Shall I be mother?"
To my knowledge, the Bible only quotes about two men engaging in sexual contact, not women.
Even Queen Victoria had to have it explained to her what a lesbian was.
Of course, many people believe in the teachings of the Bible and I would never for one moment denigate those beliefs despite being an atheist myself, but it was written centuries ago and, many today have made our own decisions about what is right or wrong, without us having to be told like we would be little children.
A christening certificate is NOT a legal document, whereas a birth certificate is.
Personally I don't care what a person's sexual orientations are and I don't think it's anybody else's business. There are many heterosexual parents who aren't fit to have kids so, as long as homosexual people can give a kind, caring and gentle home to a child, then who am I to judge them.