Overnight visits have always been a rite of passage. “They’re very beneficial to help children progress along the spectrum of normal independence,” says Barton D. Schmitt, director of the Sleep Disorders Clinic at The Children’s Hospital in Denver. But these days, parents who send their young children off to someone else’s house are often the ones who lose the most sleep. A homesick kid who begs to leave early used to be the biggest problem–and it still is, especially for the littlest guests. But now there are also so many new issues to worry about: guns or drugs in the hosts’ house, parents who leave an older sibling in charge, a violent or explicit movie on the VCR. Here are some guidelines to ease everyone’s nightmares: Hold a dress rehearsal. A relative’s house can provide an excellent training ground. Chicagoan Donna Mendicino just bought an inflatable bed for her sons, Joey, 7, and Anthony, 4, to take to their first sleepover later this month–at their grandmother’s house nearby, so they can get used to the idea of being away. Some parents introduce their children to sleepovers by letting them participate at the other house in all the traditional activities (through teeth brushing) but then whisking them home to their own beds. This popular practice–called a “dayover,” “sleepunder” or “undernighter”–can help prevent that midnight phone call to collect a homesick child.

Be informed. Make sure the host family is responsible and the house safe, says University of Chicago child psychiatrist Bennett Leventhal. “If you think they’re going to be damaged, you shouldn’t send them.” Ask the host parents about their plans for the evening. If it’s a coed sleepover with older kids, supervision is even more important. Will the parents be home all night or will a babysitter or older sibling be in charge? Tell the parents about your child’s rituals, such as using a night light. Make sure your child knows where the host parents’ bedroom is located in case he needs help.

Pack properly. Loading a flashlight, a toothbrush, a special pair of pajamas and other vital supplies into a beloved Tweety Bird suitcase is half the fun. Remind your child to tuck in his special comfort object-“or else you’ll be driving it over when the child’s going to sleep,” says Boston pediatrician Hanna Sherman, whose daughters, 8, 11 and 14, are frequent hosts and guests. If your child feels embarrassed about toting along a stuffed animal, read her “Ira Sleeps Over,” Bernard Waber’s classic about two boys who are afraid to let each other know that they curl up with a teddy bear.

Plan the night’s activities. If you’re the host, map out an agenda. During the summer, haul out the garden hose and buy some water balloons. Hallie Warshaw, creative director of “The Sleepover Cookbook,” encourages guests to bring along photos of themselves as infants so that their friends can play “name that baby picture.” For more ideas, check out gamekids.com, which suggests themes such as a teddy-bear sleepover (bring your favorite stuffed animal and hide it) and paper-airplane night.

Break a few rules. “Children must have occasions when they stay up until 4 in the morning and eat candy until they burst,” says child psychiatrist Elizabeth Berger, author of “Raising Children with Character.” “The routine is only wholesome when there is a break that can be celebrated.” If you’re hosting a group sleepover, stock up on groceries and think in terms of dozens and gallons. Elaborating on a staple is always good entertainment. Make breakfast pancakes in funny shapes or provide ingredients for a (decaffeinated) tea party.

Keep sleepovers a special occasion. They’re not meant to be an every-weekend activity. “We don’t do it on school nights or before big events,” says Sherman. Some coaches are even beginning to prohibit sleepovers the night before games. Children need to get at least eight to 10 hours of sleep a day–hardly the practice during overnighters, when excited kids crash late and, mysteriously, seem to wake up unusually early.

Finally, if the war-zone decor on the morning after makes you want to skip this coming-of-age ritual, remember the allure of whispering into the wee hours with a friend while snuggled into sleeping bags. And try to smile, not groan, when you hear those midnight giggles. Those are memories in the making.