How to get a child to go to sleep–and sleep through the night-can be an exasperating riddle. It’s certainly one of the most important to solve. Good sleep is crucial to good health: most growth occurs during sleep. Children who don’t get enough sleep are less alert during the day and therefore more prone to accidents. And a sleep-deprived child is going to be crabby and impatient. Half of all children under 6 have, at one time or another, some kind of sleep difficulty, according to the nonprofit National Sleep Foundation, an informational clearinghouse. Small wonder that parents scarf up books, gadgets, videos-anything-to help get their children to sleep. They’ll find, unfortunately, that even the “experts” can’t agree on the best strategy.

For years, Dr. Benjamin Spock’s classic “Baby and Child Care” supplied the conventional wisdom on all aspects of child rearing, including putting fussy children to bed. If they won!t sleep, Spook suggested, let them cry it out. Fifty years later, Spock’s advice hasn’t changed much. Even the 1992 revised edition recommends putting a fussy baby to bed, leaving the room and letting him “cry furiously” until he falls asleep. In three nights, Spook promises, Baby will have learned his lesson. Make exceptions, and you’re asking for a hard day’s night.

Tough Love

NOW FERBER, HEAD OF THE CENTER FOR Pediatric Sleep Disorders at Disorders at Children’s Hospital in Boston, has taken over as top guru on children’s sleep issues. His 1985 book, “Solve Your Child’s Sleep Problems,” has, over time, become the strategy manual for bleary-eyed parents flummoxed by bedtime battles. In a sense, Ferber preaches a gentler version of Spock’s tough love. Infants and toddlers learn by association, he says: teach a child he can fall asleep only while being held, rocked or fed, and he’ll insist that those conditions be met night after night. Teach him he can sleep on his own, and he’ll do that. If an otherwise healthy child fusses in the crib instead of going to sleep, Ferber advises parents to give the child a reassuring pat (not a comforting cuddle) and leave the room. If the crankiness continues, they should return and calmly reassure the child. Ferber suggests doing this at increasing intervals–5 minutes at first, then 10, then 15 and so forth. Within a week, the child should be trained (“Ferberized,” as fans call it) to fall asleep on his own. “Bedtime should be a happy time,” says Ferber. “Not just for babies, but for parents, too.”

Not everyone is sold on Ferber’s methods. Some doctors, like pediatrician and child-care author William Sears, criticize the seeming insensitivity of letting a child cry himself to sleep. Sears, coauthor of “The Baby Book,” argues that babies should be “parented to sleep, not just put to sleep.” Parents who resort to a strict bedtime program, he warns, fail to address the reasons for a baby’s restlessness, which can include insecurity or physical discomfort. In doing so, they risk losing an infant’s trust.

Some specialists say the big sleep conundrum is a question not of how but where. For most of human history, having babies, and even toddlers, sleep in the family bed was the norm in most cultures–and still is outside Western societies, says James McKenna, an anthropologist at Pomona College in California. “Co-sleeping” he says, is naturally convenient for babies who are breast-feeding. Newborns also rely on proximity to their mothers to help regulate body heat, breathing and cardiac rhythms. In fact, McKenna’s research suggests that co-sleeping may, in theory, reduce the chance of sudden infant death syndrome: a mother’s tossing and turning will keep a baby from having long pauses in breathing, a suspected cause of SIDS. “Babies’ bodies are designed to sleep next to their mothers,” says McKenna.

Most experts frown on co-sleeping for a variety of reasons. For one thing, children are restless sleepers. They kick, clutch, grab and poke. That may make it tough for parents to get the sleep they need. Then there’s the potential loss of intimacy. “Co-sleeping can disrupt your entire life,” says Deborah Telchin, a New York pediatrician. “Your life shouldn’t be totally dependent on your baby’s sleep habits.” Once co-sleeping begins, it may be hard to get a child to sleep on his own. “The older a child gets, the harder the habit will be to break,” says Fairleigh Dickinson psychologist Charles Schaefer, coauthor of “Winning Bedtime Battles.” “There are better ways of solving sleep problems.”

Dream On

A LITTLE UNDERSTANDING OF the science of sleep can help make a baby’s restlessness easier to deal with, too. Although every child is different, newborns usually sleep 16 hours a day or more. But infants have shorter sleep cycles with more periods of light, dreaming (REM) sleep. In fact, 50 percent of newborns’ sleep is in the REM state, twice as much as adults’. They rarely sleep more than a few hours at a time and take a longer time to fall into deep, non-dreaming sleep. Eventually, babies develop adultlike sleep patterns-and weary parents can expect more rest. By the 6-month mark, infants will have learned to sleep for longer stretches, especially after giving up night feedings in the fourth or fifth month. Toddlers, too, experience much more active sleep: one third is typically in the REM state, which can account for more night wakings.

So what is the best way to turn bedtime into happy time? Groups like the American Academy of Pediatrics suggest, for infants, warm baths and soothing massages to lull them to sleep; the white noise produced by running water, a fan or a metronome might do the same. Soft music works, too. (Studies show babies like classical best.) For toddlers, establish a regular bedtime routine that might include a quiet activity, such as reading a bedtime story or playing with a toy to help the child unwind. As sleep specialist Dr. Mary Carskadon of Brown University says: “Families need to find a plan that works for them, one that gives the children, and their parents, adequate sleep.” No fuss from us about that.

46% of those who are in two-parent families say they and the other parent share equally in getting up at night when their child cries.