Here are the developments for a 2 month - 4 week old baby, based on babycenter.com

Hands on

Your little one first discovered her hands a couple of weeks back, and now she's downright fascinated with them. Watch as she examines them, puts them in her mouth, and tries to suck on them.

Don't worry if your baby becomes a bit obsessed with her newly discovered digits: This form of self-comfort can be very soothing for your baby — and can possibly give you a little break, too.

Steady now

This week, when you go to pick up your baby, she may be able to lift her head and hold it up for several moments, or even longer, while lying on her back. When sitting with support, she should be able to hold her head steady and erect.

When she's on her stomach, you might see her lifting her head and chest to about 45 degrees as if she were doing mini-pushups. You can offer encouragement by sitting in front of her and dangling a toy.

For a fun game that also develops her neck muscles, place your baby on her back and slowly pull her up by her hands to a sitting position. Slowly ease her back down, and repeat. She should be able to hold her head in line with the rest of her body as it's pulled up.

Your baby may be ready for a jogging stroller at 4 months, but stick to smooth pavement for now. Running trails will be too bouncy for her at this point, unless she can hold her head up well and is able to sit up. When her head is steady, she may be ready for a backpack with good support and a headrest.

Reading 101

Reading to your baby, even at this young age, will pay off. Hearing you read helps your baby develop an ear for the cadence of language. Varying the pitch of your voice, using accents, and singing will make the connection between you and your baby that much more interesting.

If she looks the other way or loses interest while you're reading, just try something else or give her time to rest. Take your cue from her responses.

You'll find plenty of good books to read to your baby — such as Goodnight Moon, Good Night Gorilla, and The Big Red Barn. Choose board books that have large, bright pictures and simple text — or even wordless books that have pictures for you to narrate. At this point you needn't be slavish to age guidelines. Books designed for older children can captivate a baby if they have clear, crisp images and bright colors.

You can even read out loud to your child from something written for adult ears — try reading from the newspaper, your favorite novel, or a magazine. Whether it's Shakespeare or the latest bestseller, if you enjoy reading it, your baby will like hearing the rhythms of your voice.

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So far, baby has experienced these already. She has already learned the act of thumb sucking (or should I say, hand sucking). She does this when no one is looking at her or when she is waiting for her milk. In addition, she can already lift her head for longer period of time. She lifts it especially during her tummy time.