In the first video, Kate looks a bit tense(It's her mouth that clued me in, although maybe it's visible in her eyes too), and her smile and general mood seems a bit forced. Some of her mannerisms make her look nervous(most people would be).
Second video: Affection, pride, both? I'd say mostly affection, although that phrase is also often associated with pride.
Third video: I didn't really pick up on anything.
