I had triplets (two boys, one girl) in my ATOR legacy (the one I actually write a story about) but they were generation L and they had parents, grandparents and a teenage uncle to help with them, so it wasn't too bad. All three learned their skills and grew up well.
I also had a set of triplets (all girls) in an undocumented 10-generation legacy in Veronaville. Generation 6, parents and grandparents around, once again there wasn't an issue. These ones did have an older sister, but she was already a child by the time they were born, I think. When I got to generation 10 in that legacy, though, the heiress and her wife had
quads. Three girls and a boy. Even with parents and grandparents around, things weren't that easy this time around, though they did end up learning all toddler skills and growing up well. The best/worst part about this family in particular was the fact that after the quads became teens, I decided to let their mothers have one more child, because the grandmother, a sim I like very much, was close to death and had a want for a grandchild. Guess what - yes, quads again! (three boys and one girl this time) Considering that there's only a 5% chance of quads for every "random choice" birth, maybe I should play the lottery?

I haven't played that house since the second set of quads were born - maybe I will play them again one day. The house now has a total of 12 sims.
