noodle

It's funny, I work with kids, was a therapist for years working with kids who are acting out, have horrid manners, etc. I actually set my own boundaries with them directly in front of their parents and have actually said in front of a mother, "I'm not sure how you guys do things at your house, but here we don't ___________ [insert action, word usage, etc.] and if you choose to do _________ then you are going to have to wait in the car until your mom and I are done here." The mother got really pissed, but I explained that every home and person has their own rules and I choose how I allow people to treat me and my belongings.
There are other ways to handle it, but I typically address the child's behavior and explain what I expect directly with them in a positively-reinforcing manner. Then I talk to the parent separately and explain to them what I'm doing: helping a child learn what is socially acceptable when I'm around. I won't be hit, my couches won't be jumped on, my cats' tails won't be pulled, and I won't be called names. But I'd be happy to sit on the floor and play, or sing silly songs if they would like to act appropriately.

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