They do what villagers do, and that is being available to chat, trade and play tag.
The kids have been told NOT to jump on the farm, since they were so poor and weak a few months ago so they shouldn't jump and/or trample (run) on the small farm. They play tag every day and chat each other every night. They seem to get better and better at playing tag.
AdultEditThe adult seems to be a priest from the church. He is a semi-priest, which means he is almost a priest and trains to be one. His nature is relaxed, and calm.
It appears that the adult only trades:
1 emerald for 2 glowstone (added 12/16/12)