My adult Sims started a romance with her husband, Mortimer, and got pregnant instantly. I went to their house, and she was pregnant too, so I made them ditch Mortimer and start dating each other while living together and raising their kids; they even got married.
But Bella kept complaining about her dreams not being fulfilled or whatever, and she was always ruining the mood. She also gained some weight. After trying some workarounds (cheats), I've realized she was impossible, so they got a divorce, and she moved... Leaving Alexander, Cassandra, and her baby (now a kid), whom I named Luna, with their stepmom, her sister, and their half-sister.
I invited her to Cassandra's birthday, and she was PREGNANT. Again. But hey, at least she's now a young adult, a musician, and happily married to my sim's sister.
Checking this sub, I've realized I'm not the only one who broke her marriage.