yeah she is tickled in 'Ferris' and he totally goes for her feet but you can't tell in the shot. If you look at his hand placement though during that scene, you can tell it's definately NOT a knee squeeze. Also i vaguely remember on one of the ticklish celebs list (ironic's maybe) sayin that it was quoted in some teeny mag like teenbeat or tiger that Broderick did tickle her feet to make her laugh like that.
Hope that helps
Piz
Of course that's just my opinion, I could be wrong.