When it starts: Around 6 months
What's going on? When your child was an infant and she dropped a rattle, she assumed it was gone. Now she realizes that things exist even if she can't see them, a concept known as object permanence. You'll know it's kicked in when she looks down to see what she's dropped from her high chair. "It's a game for your baby, and it teaches him about cause and effect -- 'I drop it, you pick it up,'?" says Tovah Klein, Ph.D., director of the Barnard Center for Toddler Development, in New York City.
Get past it: Although it's tiresome to pick up utensils, toys, and Binkies all day, humor your child for a while. "She'll feel empowered every time you respond," says Dr. Klein. Feel free to end the meal once she knocks over her bowl of mushy carrots. Fortunately, the novelty of falling sippy cups will wear off by around 15 months.
When it starts: 7 to 9 months
What's going on? You think your baby's goal at lunch is to eat? Ha! A meal is entertaining for other reasons. Soggy Cheerios make an agreeable noise as they squish through her fingers, and sweet potatoes feel good on her cheeks. Your child is also exerting her independence. "There's very little that babies can control, so when they play with food, they're examining it on their own terms," Dr. Klein says.
Get past it: Resist the urge to take away her spoon. Your child needs to practice feeding herself. By her second birthday, her coordination should improve and she may be more focused (and less silly) at mealtime. Still, don't be shocked if your kid remains a sloppy eater until kindergarten.
When it starts: 7 months
What's going on? Your baby is suffering from stranger anxiety. Although he may once have been fine with being passed around at a party, he's now aware of whom he does and doesn't know. He may freak out when you hand him to a grandmother who doesn't visit regularly or even when you open the door for the UPS guy. Embarrassing? Sure. But the ability to distinguish you from someone unfamiliar is a developmental leap forward (and you should try to explain this to your in-laws so they don't take it personally).
Get past it: Help your child warm up gradually to strangers until this phase passes, which is usually around 15 months. Alicia Weir, of Ann Arbor, Michigan, used to let a friend hold her 8-month-old son, Mosie, as soon as she arrived. "He'd look at me with fear, his little lips would quiver, and he'd start crying," she says. Now Weir has Mosie sit in her lap until he's ready to get acquainted. If you try this method and the tears still start rolling, don't reach for your baby right away. "Have him and your friend get involved in an activity together to see if that will make him feel secure," suggests Claire Lerner, director of parenting resources at Zero to Three, an early-childhood-education group in Washington, D.C.
When it starts: About 9 months
What's going on? Your baby could be about to hit a major milestone, such as standing or cruising. "While she's channeling all her energy into this skill, she may regress in other areas, including sleeping," says Dr. Klein.
Get past it: Comfort your child quickly, and then leave the room so she falls back asleep on her own. The longer you stay, the more stimulated she'll get. Also make sure you're following a healthy bedtime routine. Put your baby down for the night while she's still awake. Her good sleeping habits should resume within a few weeks.
When it starts: Around 8 to 9 months
What's going on? Your child realizes that Mommy and Daddy have distinct caregiving styles, and he's expressing his preference for one over the other. In most cases kids pick the parent with whom they spend the most time. But if your spouse turns everything into a game or bends the rules more often, he may become your baby's go-to option.
Get past it: Be patient if you're the one being rejected. Your baby may switch back soon. Besides, forcing yourself on your child may cause him to resist even more. Instead, try to spend more time as a threesome. Gradually the favored parent should pull back so the one who's feeling snubbed can get more involved. It's also a good idea to take turns doing feedings, baths, and the bedtime routine, so your child won't associate any of these with just one of you.
When it starts: 9 to 12 months
What's going on? Your child is gaining greater control over her body. So instead of just lounging while you put on a diaper, she's busy testing her new kicking and turning skills.
Get past it: Find a way to distract her. While a toy or a book may work, babies are fascinated by everyday objects. Melanie Hochberg, from Maplewood, New Jersey, says that clutching a bottle of lotion is the only thing that keeps her 9-month-old son, Silas, from flipping like a seal on the changing table. Sometimes even that doesn't work, and she has to hold him down with one hand and switch out a dirty diaper for a clean one with the other. You might have better luck changing your baby on the floor, so she has more room to move and you won't have to worry about her falling.
When it starts: As early as 9 months (but it's often worst at 10 to 18 months)
What's going on? Separation anxiety kicks in when your child can picture you in her mind even when you're not there. Need a little privacy in the bathroom? Good luck. She hates to say goodbye because she doesn't know how long you'll be gone.
Get past it: When you need to check on dinner, keep talking so she knows you're close by, and make a big deal when you return ("Ta-da! See, I told you I wouldn't be gone long"). If you're going out, have the sitter come early so your child adjusts to the idea. Then give her a kiss and say, "Good night, sweetie." Long goodbyes tend to confuse and upset young kids. Babies who are used to having other caregivers tend to get over separation anxiety faster, but depending on your child's personality, it could linger through kindergarten.
When it starts: 3 to 4 months
What's going on? When he sucks on a toy or his toes, your child is trying to take in information: Is it hard? Is it squishy? Can I eat it? That's because your baby can't ask questions to figure things out the way you do. "His primary way of learning about the world is through his senses," says Lerner.
Get past it: Keep dangerous items locked away or out of your child's reach. This includes anything small enough to fit inside a toilet-paper tube; scissors, letter openers, and other sharp things; and poisonous substances such as cleaning products and medicines. It may help to crawl around and see what hidden hazards lurk at his level. If your baby puts something tiny in his mouth, remove it at once and give him something safe to gnaw on instead, such as a board book or a blankie. While there's nothing you can do to stop his oral fixation, this stage usually starts to fade around 12 to 18 months, when your child turns his attention to walking and talking.
If your baby is acting super-cranky, napping inconsistently, or eating nonstop, she may be going through a growth spurt. This phenomenon occurs when the pituitary gland produces bursts of hormone, which stimulates a baby's body to grow.
Spurts generally happen at around 2 to 3 weeks, 4 to 6 weeks, 3 months, 6 months, and 9 months. Right before one starts, your baby may wake up more often to feed, which makes her fussier than usual. During a spurt your child is likely to snooze for longer stretches and might need to eat as often as once an hour when she's awake, says Jennifer Dyer, M.D., a pediatric endocrinologist at The Ohio State University in Columbus.
Since these behaviors can be caused by a number of other factors, look for this telltale sign: If they persist for only a few days and nothing else seems to be bothering your child, you can safely write it off as a growth spurt. Any longer than one week, and it's worth calling your pediatrician.
Originally published in the August 2010 issue of Parents magazine.
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