I found certain traits wont use it, family oriented being one of them, my whole dynasty family ended up getting that trait in the end and it stopped it completely.
According to the code loser or mooch wont do it either but genius, snob, mean spirited and perfectionist will regardless of nerd influence. I had a family oriented genius in my game and she never did it so it seems it trumps the special trait interaction as well if you give them one of those three traits.
I know it's not necessarily ideal to have to change traits, I used the social trait or degree on the adults and any kids got it while aging up, but it totally changed my game and made it enjoyable once more as they were driving me nuts with that action, and you can let them be as nerdy as they like with no worries