My son has been having a lot of medical assessments lately since he's slow to talk. Inevitably I get asked if I'm his mother. I have to register him for kindergarden soon and the forms there also have one space for mother, one space for father, and a space for legal guardian (I don't want to put legal guardian). He has two biological dads which can get confusing if we both call ourselves "dad." Also, I'm afraid I'd have to explain everything when I just want to get on with the issue at hand.
What do I answer?

Edge, I'm getting this more and more too.

For me, I say "Yes, I am his/her parent," in response to that. Deflects most inquiries. I introduce myself as "Suzi, R____'s parent."

I haven't got a lot of intrusive stuff, but if someone asked whether I was the mother, I would probably answer something like, "Yes, I am one of her female parents." Most people would just assume we're lesbians raising a kid together.