There seems to be an assumption in your post that kid!fic has to be slash fic. So, for me the thing is Kid!fic seems so acceptanle in hetero but not homo situations. But for me, if it's heteropeople OR homopeople that I can SEE - like Ray - would like to have kids, I can handle it. Otherwise, no thanks. It's all about characterization. I mean, I think Harry would want kids, and I think I like reading H/G where they have kids. I am not sure about either Remus OR Sirius wanting kids, and since that couple is dead, given, you know, one of them is dead and the other has moved on, then I don't really want to read kid!fic with them. On the whole, though, MPREG is stupid. I don't like fic in which things that are anatomically impossible happen. Poorly written sex, for example. Or MPREG.