Case solved.
It turned out there were quirks notified, but that the list was full so I had to click them to see them. There were several infant quirks, so I take it that aging the infant in CAS caused it all. Hoping it will calm down when all related quirks were discovered. Or, maybe if I revert age in CAS and age the infant up to toddler by cake, then age up to YA in CAS. Never had a similar situation, so i assume it is limited to the infant lifestage.
Anyway, it's good to know it is nothing that can spread in my game.
Thanks for helping out!
easiest is to just remove the quirks with a mod.
I'll merge this.
