Celery

Laura: Mommy, I never had these green things before, so I tried them. I don't like them.

Thus fulfilling all requirements to not any more. Ok.

Karen: _ignore the green things and Mommy may not notice that I didn't try them..._

Karen, you have to at least try the celery.

David: Ah, ah, ah!! [interpretation: Mommy, I really liked these green things. May I have more even though I didn't finish the carrots on my plate?]

You like the celery? Good job! Don't forget your carrots, though.