One time in a masterwork fortress in 0.34 I got a dwarf that was schizophrenic. I didn't know what that would do, but I just assigned her to machine operating, also known as ore refining in masterwork. She did really well, she was one of few dwarves that I kept track of regularly, I think she reached legendary. At some point she had a child though I don't remember when that really happened. Then one day she went crazy or something, I'm guessing schizophrenia in masterwork just adds [OPPOSED_TO_LIFE] eventually, and she started punching her child, she didn't really do any damage though. They were both in the forges and were the only ones there. I was really confused and unsure what to do, but I think her and her child left the forges before I could react, and my forges are right next to the barracks, so the guards came out and swiftly killed her, and then her child as well due to loyalty cascade. The child ended up saving the fortress though, because when the machine operator went crazy I guess she was still a member of the fort and civilization, so the first dwarf she got in a fight with would similarly end up an enemy of both, and if it wasn't her child it would have been military and a crazy dwarf and her child being the enemy of your fort is better than a crazy dwarf and a full legendary steel armored soldier.