I always have last exceptions in my sims 4 folder, usually 2 or 3. I make sure to delete them before restarting my game. Is this the same for everyone? I am a totally vanilla player.
I usually get them with MC Command Center. It is just small error files in your game. I've only had them happen due to mod clashes, or outdated mods, but never a fully vanilla game. My last exceptions used to prevent my kid from sleeping. If it gets to a game breaking level like almost getting your child taken away, I would try to investigate, or read it with Pretty Print XML.