Congrats to Lena and Christina!
For the record, out of the 13 pregnancies, I had 4 sets of twins. The first pregnancy was twins; I purchased fertile for both afterward; didn't have twins again until dad was an adult ;P This wasn't surprising for me, as I've played a baby challenge in the sims 4 before and know fertile is incredibly broken. This actually made me more comfortable with starting some of the more difficult aspirations first.
Like ClayMask, the only kids of mine who ever went to school were the whiz kids (who were carefully chosen so they would have enough school days to get an a without having to wait the weekend.) The only teen who went to school was the Renaissance Sim, and only for the two days to get an A and the career boost. I actually gave my kids a variety of child aspirations until the very end, where everybody was run through Artistic Prodigy- Matriarch + Encourage Interaction + Very Inspired makes it a joke. The kids maxed their creativity before they got to playing the violin, so I had my Musical Genius or one of her brothers come over and mentor them for the five hours. They had level 5 or 6 violin skill before they were even teens.
Two weird things I haven't seen listed yet, both related to the house. I use the term "house" lightly- every family member was given Loves The Outdoors, and the house was an inspired room, a focused room, a dry room that could have a random mood object thrown in it, and a room that shifted from playful to energized. These rooms were separated by a wall or two to keep the mood objects from seeping from one to another, but were otherwise completely outdoors, giving a constant 2+ happy moodlet to the family. The only rooms walled off were the bedrooms (as in, rooms with beds in them) and the bathrooms- three two tile rooms containing toilets and three three tile rooms containing showers. That brings me to the next point- there was no sinks on the lots. Sounds random, but it's actually a good time saver, as you don't have to worry about sims wasting time doing silly things like washing their hands or the dishes.
My main downfall was not doing enough forward thinking; there were many times when I would completely forget about a difficult or time consuming requirement on the last part of an aspiration and panic. If I had done the aspiration of my last teen (Freelance Botanist) first instead of last, I would've easily accomplished it. I would've easily accomplished Fabulously Wealthy on my other teen if I'd had the dad painting his butt off mid challenge instead of just twiddling his thumbs. Oh well, I learned a lot for next time!
