Really fun concept for a card game! The randomness of the cards felt a bit unfair, as I got 2 -8 happiness right at the beginning of the game. However the idea and art were good and kept me playing still. If I were to also nitpick it felt weird that each smile icon is equal to 2 happiness instead of 1.
The keep one card mechanic was very nice to add some strategy to the game, but it still didn't feel like a real choice to make, as the answer was always at best obvious or otherwise not important.
All that said it was a fun game, and I am nitpicking out of my enjoyment, great job!