At the beginning of the film yeah Tiana.

I think Pocahontas will win this pick despite her not being that serious at all, she in fact mocks seriousness in her film and she is just always represented looking thoughtfull and serious when she is actually a pretty playfull unserious princess.

To the point where it's annoying, really.

I think Pocahontas has more moments of being carefree than Tiana does.

Pocahontas always had these cool, thoughtful, and serious looks. Though she was quite playful. Tiana would mostly get happy if she was talking about that old building and envisioning her restaurant. Other than that, she didn't have fun. Toward the end of the movie is when you see her dancing and having fun with her friends.

Ironic considering she claims this is why she doesn't like Kokooum. I think she's serious because she needs to be...her film has heavier themes than all the other princesses.

Poca's movie is more serious, but Poca has her playful moments in her film. At the beginning Tiana is so serious in her movie, so I pick her.

well i havent seen Princess and the Frog so out of all of the princesses (excluding Tiana obviously) i think Poca is the most serious. maybe Cinderella.

at first, Mulan seems kind of silly, but the whole time Jasmine is serious.

The most serious one isn't Poca, it's Tiana. Poca shown playful side in some moments.