Hidden Traits

Is this a hidden trait, or just a random moodlet? I made my sim swim in the pool after this one expired and she got the normal happy pool buff. Wasn't sure if some sims are just randomly hydrophobes.

https://i.imgur.com/j8N5CBv.png

Anyway, what other hidden traits do you know of in the game? I know that for City Living, there's the Spice Hound and Chopstick one, and I know that there's a hidden left handed or right handed trait. Also sims will either hate or love fruitcake and will get a corresponding moodlet. Curious to know what other hidden traits you have discovered!