Helping your baby feel secure and engaged in the world now can help her achieve emotional health and mental aptitude as she grows. Doing this is surprisingly simple at this age:

• When you soothe and calm your fussy baby, the message she gets is: All is well with the world. It’s a message that stays with her as she grows.

• When your baby is stressed, help her relax by gently stroking her back, arms, or legs from top to bottom. (This is baby bliss.)

• Before bedtime, sing to your baby or rock her so she associates bedtime with peaceful time.

As a mom, you’re the center of your baby’s world. You’re her source of emotional and physical security, and mental stimulation. Fortunately, there are some simple ways to entertain her:

• Run a shallow bath of warm water, and watch her splash, kick, and enjoy (while you stay near, holding her tightly and keeping her safe).

• Ensure that she always has a good view — sit her in safe positions where she can see everyone and everything going on around her.

• Encourage baby vanity, and spend some time mirror-gazing.

Now is the month when your baby’s playful side may come out in full force. Now’s the perfect time to reconnect with your inner child. Help her learn while she’s playing with:

• Activity boards that encourage her to push, pull, turn, and poke bells, wheels, and dials

• Cloth, wood, or plastic blocks that help show your baby how to build towers (and how to knock them down!)

• Toy telephones, spoons, and measuring cups that introduce her to common household objects

• Hand games, such as the classic “pat-a-cake,” that help her practice her fine-motor skills.

It may seem like the change happens overnight — on Monday, your baby needs help sitting up, and on Tuesday she’s sitting up for the first time on her own.

In reality, your baby has been silently working for months to sit up on her own. She’s been strengthening her muscles by sitting in her infant chair and by sitting propped up against pillows.

While the first time she sits tall, she’ll be leaning on her hands for balance, in the next two months, she will sit completely by herself and use her hands to play.

Last month, your baby’s first fear may have emerged — the fear of strangers. This month brings a new one — separation anxiety. This fear typically begins at 6 to 8 months of age. This is when your baby becomes aware that you’re separate from her, and this means you can walk away at any time.

If your baby cries when you leave the room, or wakes up in the night crying and refuses to go back to sleep this month, she’s probably suffering from separation anxiety.

Because your baby’s real fear is that you’re going to leave and never return, the best way to alleviate her fears is to leave, then return, repeating the pattern, until she realizes you’ll always come back.

To make this fun, play “peekaboo” — go away and come back before the fear gets too strong. Then have fun watching the ecstatic look on your baby’s face when you return.

Once your baby is 6 months old, she'll begin sleeping through the night. But she may still occasionally wake in the night. At this age, if she still wakes up several times a night, talk with your health care professional about possible causes and solutions.

During the day, your baby will be wide-awake and active for extended periods, taking two or three short naps totaling three to four hours.