I kind of had a bit of happy glitch too (well maybe kind of bittersweet hehe). I already had 90 total population which is supposed to be the maximum you can have (that's what it told me anyway), but then one of my elder villagers died and so I grabbed one of my younger women and put her and hubby together to make another baby (to make the total population 90 again) and she got pregnant with twins, so my total population was 91. Although, that didn't last very long because then one of my other elderly villagers died, so the population was back to 90 again. She hasn't released her twins yet, she's still caring for them. I have one woman villager who is caring for triplets. I thought I'd never get twins or trips LOL.

Edited because I forgot to ask: Are the twins/triplets always of the same gender (and identical)? Or are they sometimes like one boy, one girl?