5-Month-Old: Week 1

Your baby will soon master the art of sitting up unsupported. Give her the opportunity to sit up in different places, and take her on outings in a stroller. The time your baby spends sitting up helps her develop and maintain balance, a key part of her physical development. What's more, making use of the new perspective helps her cognitive development, too.

How your baby's growing

Your baby can't express his emotions in the same complex way that you can. Although he can let you know in clear ways when he's angry, bored, or happy, his ability to show love and humor are just developing.

Your baby also shows a strong attachment to you by raising his arms when he wants to be picked up and by crying when you leave the room. He may also give you hugs and kisses.And he's beginning to get the joke — he'll laugh at funny expressions and try to make you laugh, too. Keep the laughter flowing with your silly faces!

• Learn more fascinating facts about your 5-month-old's development.

Your life: Sex as new parents

Finding the time and energy for sex as new parents is challenging enough. And then there's the small matter of the third party in your room or down the hall, ready to wail at the least opportune moment. But with a little planning and effort, anything is possible!

Flirt. Flirting isn't the same as foreplay. It's sexual play without the intention of immediate sexual activity. Flirting with your partner (in person, on the phone, or by e-mail, for example) helps both of you get in the mood.

Time it right. You don't always have to "sleep when the baby sleeps." At nap time or bedtime after your baby's had a busy session of play or outside activity, you can feel pretty assured of your baby's sleeping for at least an hour.

Make a "date." You don't have to dress up and go out — simply plan ahead to stay in. When you're parents, sharing massages or taking a shower together while the baby sleeps counts as a date.

Keep a sense of humor. Be ready for things not to go as usual. If you're breastfeeding, for instance, you may see some milk leak or spray (so have a towel handy). If your baby does start to cry, don't rush to her rescue; wait a few minutes to see if she settles back to sleep. If she does settle down, you may find that the mood has been broken anyway. Don't call the whole thing off. Start back with slow, gentle foreplay and see what happens.

3 questions about: Your baby's noggin

Should I do anything if my baby's head looks flat?
A flattish head is usually the result of sleeping too much in one position and isn't a cause for concern. Mention it to your doctor, who can evaluate it. In rare cases, a specialist may advise treatment such as cranial orthotic therapy involving headgear. Flattish skulls have become more commonplace since babies began to be placed on their backs to sleep to prevent SIDS. Although the condition is harmless, some parents look into pricey helmets to prevent or correct flatness. You can do the same by giving your baby "tummy time" during the day to play and alternating at which end of the crib you place your baby's head. (Even when lying on their backs, babies tend to turn their head away from the wall to look around.) Flatness usually goes away as your baby grows.

What should I do if my baby is losing hair or has a bald spot?
Again, it's the situation your baby finds himself in, not a serious health problem, that causes most baby baldness. Keeping his head in the same position, rubbing it against his mattress, or banging it against the sides of his crib may cause some hair loss. This stops when he eventually changes his behavior. Babies born with lots of hair often lose it as hormone levels drop. It's very rare for a baby younger than 6 months to have other causes of hair loss, such as the autoimmune disorder alopecia areata or ringworm.

When will my baby's hair grow in?
This is hard to predict. Some babies grow in new hair soon after the old is lost, while for others it seems to take longer. The color and texture of this new hair may be significantly different from the hair your baby was born with.