17 Totally Outdated Pieces of Baby Advice

The truth: Babies don't get stinky from sweat the way adults do, so they only need a bath every two or three days (except following a major diaper explosion!). If it's part of your wind-down routine, a daily bath is perfectly okay too—just moisturize afterwards.

• RELATED: This Is How Often You Should Bathe Your Baby

The truth: While some children really are light sleepers, most do fine with background noise and a little light. Plus, if your little one gets used to some activity around him when he's sleeping, he'll be more willing to snooze in a variety of situations.

The truth: Rubbing your baby with alcohol won't actually bring down her fever—plus it's unsafe, since alcohol can be absorbed through her skin.

• RELATED: How To Treat Your Baby's Fever

The truth: He won't become bowlegged; that's just an old wives' tale. Moreover, young babies are learning how to bear weight on their legs and find their center of gravity, so letting your child stand or bounce is both fun and developmentally stimulating for him.

The truth: Music can enrich a little one's life, but no conclusive research has found that having a baby listen to classical music in particular can result in significant brain-boosting benefits.

The truth: Babies under 4 months of age have few self-soothing strategies; they know how to suck to soothe and like being swaddled, but that's about it. Picking infants up when they cry helps them learn that parents will always be there to take care of them.

The truth: Urine is sterile, and today's diapers are highly absorbent, so it's fine to leave a baby in a wet diaper overnight. However, staying in poopy diaper for too long can cause a UTI or a bladder infection, especially for baby girls—so if you smell one, change it out.

The truth: A minor illness won't lower your baby's immune-system response to a vaccination, or increase his risk of any nasty reactions from a shot.

• RELATED: 8 Reasons Parents Don't Vaccinate (And Why They Should)

The truth: The risk of skin cancer down the road from sun exposure is greater than the risk of your baby having a reaction to sunscreen. It's best to keep her away from dangerous UV rays as much as possible from 10 A.M. to 4 P.M., but put on sunscreen with at least 15 SPF if she'll be in the sun. The AAP says that it's fine to apply a minimal amount of sunscreen to small areas, such as a baby's face and the back of the hands.

• RELATED: The Best Baby Sunscreens

The truth: Sterilize bottles and nipples when you first take them out of the package--but after that, washing with soap and water is fine. Babies are exposed to many more germs than those that remain on a well-scrubbed bottle or nipple.

The truth: The safest sleep position for a baby is on its back. In the past, doctors worried that babies might choke on any spit-up if they weren't lying on their tummy or side, but studies ultimately linked these positions to higher rates of SIDS.

• RELATED: New Ways to Reduce the Risk of SIDS

The truth: Hold off on introducing solids until 4 to 6 months. Research suggests that babies who are given solids before 4 months are actually worse sleepers than their formula-fed counterparts—and studies have revealed a link between the early introduction of solids and obesity later in life.

The truth: It's better to feed on demand, as infants' internal hunger cues will tell them when they're hungry and when they're full. By putting your child on a feeding schedule, you may negatively affect your little one's inborn healthy-eating habits.

The truth: Babies use their toes to grip the surfaces that they're walking on, so they should actually go shoeless indoors. To keep tiny tootsies safe outside, get a shoe with a good grip on the sole—hard-soled shoes can be too slippery.

The truth: Parents often think a baby is constipated when he's not, says Andrew Adesman, M.D., chief of developmental and behavioral pediatrics at Schneider Children's Hospital in New York. Newborns often have several bowel movements a day, but they may poop as little as every three to four days at about 2 months to 3 months of age, he says.If bowel movements are very hard and infrequent, or you see blood in the diaper, however, call your pediatrician.

The truth: When a child first walks or talks has little or no bearing on his later successes, research shows. "Many parents support the idea of giftedness at birth, but this is not supported by the evidence," says Adesman. In fact, in some cases, early "achievements" may indicate a potential problem—for example,showing an inclination to be left- or right-handed before 18 months of age (children should use both hands equally until this age).

The truth: The fontanel, or soft spot, at the front of your baby's head is a skin-covered opening in the skull that pulsates, frightening some parents. "There's a presumption of vulnerability, but the brain is actually quite well protected," Adesman says. The front fontanel typically closes at about 1 year of age, while the smaller soft spot in the back of the head usually closes at 2 months to 3 months.