Your sister’s kid has the cutest little baby face in pictures. But as he thunders through your house, pulling books off shelves and playfully squeezing his juice box into your sneakers, he’s not quite as adorable.

If a visiting child starts using your bureau as a jungle gym, don’t be shy about taking control, says Paula Spencer, author of The New Mom’s Handbook (Peter Pauper Press, $10; due out in June): “Try drawing the parent’s attention to what you see as a problem: ‘Hey, it really bothers me to have my bookshelves disassembled. Can you please make Will stop?’” Be direct and ask for the parent’s help, since it’s usually best if the parent intervenes.

If you’re dealing with a toddler or an older child, it’s OK to gently discipline him directly, says Spencer. Blame the “house rules” if you need to. “I’m sorry, Hazel. Our rule is no grape juice in the living room. Let’s make a nice place for you to sit in the kitchen,” Spencer suggests. Or, again, you could address the parent: “Our kids aren’t allowed to run in the house because these floors are so slippery. Could you ask Max to slow down? I wouldn't want him to get hurt.” Keep in mind that it’s the job of the parent — not the host — to keep the child entertained, says Spencer.

Finally, don’t forget that a baby is a baby — tearing things up is his modus operandi. But he is also easily amused with household objects, like plastic storage containers. If all he has to play with is your collection of Limoges boxes, he will, so put them out of his reach (and the plastic spoon within his reach).

And remember: Your angelic 10-year-old was once the “terrible two” poster child in someone else’s house. So stay calm, cool, and collected. And just look at that face!