Babies grow and develop at an amazing rate especially during the first year of their lives. They are born with newborn reflexes and then experience tremendous physical growth, tripling their birth weight by the age of 1. It’s a thrill to witness an infant developmental milestone, whether it be the first time their baby smiles, grabs, or rolls over. If you are interested in learning more about developmental milestones, Boston Baby Nurse & Nanny will soon be offering an online Early Childhood Milestones course.

Newborn Reflexes

Newborns are born with several reflexes that will go away in the first few months of life. Most disappear by the end of six months as the nervous system begins to mature. These reflexes help us to understand the health of the baby’s nervous system. Reflexes help identify normal brain and nerve activity so your child’s pediatrician will check for them. Reflexes are completely involuntary movements or actions. Some movements are spontaneous, occurring as part of the baby’s usual activity, and others are responses to certain actions.

Sucking/Mouthing Reflex

These reflexes are important for baby’s survival, helping them find the source of food. A baby will automatically begin to suck when their mouth or lips are touched.

Rooting Reflex

The baby turns his head toward your hand if their cheek is touched. This helps the baby find his mother’s breast or bottle for feeds.

Moro/Startle Reflex

The startle reflex occurs when a baby hears a loud noise or when he falls backward, his arms and legs extend away from his body. This reflex is most noticeable during the first month and usually fades by 2 or 3 months. Swaddling can be helpful for preventing this reflex from waking up the baby.

Grasp Reflex

A baby will grasp a finger or object when it is placed in the palm of her hand. This reflex is strongest during the first 2 months and usually fades by 5-6 months.

Stepping Reflex

Even though baby cannot support his own weight, if his feet are placed on a flat surface, he will begin to step one foot in front of the other. The stepping reflex usually disappears by 2 months.

Infant Developmental Milestones

Developmental Delays

Pediatricians use infant developmental milestones as an assessment tool to make sure a baby is making progress. Premature babies are more likely to experience milestone delays but that does not mean they will not develop normally. Having delays in some milestones is no cause for concern.

Motor Development

Grabbing (3 or 4 months)

After the first few months, babies begin to gauge where things are in space, and they can plan an action, such as grabbing a pacifier. By simply dropping something and picking it up, a baby is learning that he can manipulate things with his hands and he’s learning more details about how his toys work. He can make the rattle produce a sound, for instance, which teaches him cause and effect. Being able to grab things means he can engage more in play—whether by himself or with you.

Rolling over (4-6 months)

During tummy time (which you should supervise), the baby may lift herself into a push-up position and then start to rock back and forth or kick her feet. Then, if she’s strong enough, those movements will send her rolling over. She may get startled and cry the first time. Flipping from back to front often takes until around 5 months because it requires more coordination and strength. You don’t need to coach the baby to roll, though; just make sure she has a safe place to try it out if she wants to.

Object Permanence (6 months)

What is it about peekaboo that makes your baby crack up no matter how many times you play? When a baby understands the concept of object permanence—that even though he can’t see your face, it’s still there behind your hands or his blanket—he gets a thrill from knowing that at any minute your smiling face will pop back into view. A few months later, he’ll be able to play along by hiding himself. This is an important infant developmental milestone.

Or try sitting close enough so that your baby can see your eyes. It’ll keep him focused on what you’re doing. Ask, “Where am I?” Your voice will reassure him that you’re still there. Vary the length of time you’re hiding and play with the tone of your voice to make the game more stimulating for him and less monotonous for you!

Sitting up (8 months)

Once a baby has enough balance, arm strength, and head, neck and lower-body control, she’ll be able to sit up and take in a whole new world. At this point, her improving eyesight will allow her to see objects outside her direct line of vision—and she’ll try to pull herself up to get a better look.

At first, she won’t be able to sit up for long on her own and may need to put out her hand for balance. To motivate a baby to sit well, dangle or set her favorite toy in front of her, then slowly move it from side to side to encourage her to reach for the toy and rely solely on her torso and legs for balance. She’ll be sitting without help in no time!

Crawling (6 to 10 months)

Now that the baby is sitting up by himself, it won’t be long before he’s looking to broaden his horizons. He’ll probably start by repositioning himself, from sitting to being on all fours. Then he’ll test his arms: When he figures out that they can support him, off he’ll go. Some babies start to move without doing the typical hands-and-knees crawl. He might shuffle across the floor on his bottom, slither on his belly or even roll. To encourage him, clear some space. Then place things he likes (including yourself) just out of reach. And be sure to keep him safe by childproofing the house. Take a tour on your hands and knees and remove anything the baby shouldn’t get into.

Pulling up (8 months)

Until now, the baby has depended on you to help her get up on her feet. But at around 8 months, her torso and leg muscles will be strong enough for her to stand up on her own. It’s also when she’ll realize that she can. Her confidence has been boosted by her ability to roll over, sit up on her own and crawl.

At first, she’ll look for things to pull up on—the side of the crib, the arm of the sofa, your leg—so be sure to remove objects that aren’t safe or sturdy enough for support, or that have sharp edges she can fall on. And while she may not need to grab your fingers to get up anymore, she won’t know how to bend her knees to sit until she’s about 10 or 12 months.

Walking (10 to 18 months)

First steps represent a huge developmental leap. Walking requires muscle strength, coordination, balance—and a certain level of emotional maturity, too. After all, when you’re crawling, your center of gravity is just a few inches off the ground. To walk you need to have a bit more confidence. That’s why some beginning walkers are content to cruise along the furniture for weeks. The more eager hike away and never look back. There is a wide timeframe of when babies experience this infant developmental milestone so do not worry if your baby does not walk until they are 18 months. They will get there!

On the most basic level, walking frees up the child’s hands to carry items while he moves about independently. By incorporating everything he’s learned from all the other milestones—about space, objects and people—he can now bring you things. This turns a purely physical skill into a game, as well as a rich social interaction. For instance: He comes over to you with his little toy duck and you say, “Thank you.” You quack a few times (to his delight), and then he takes his duck away and you say, “Bye-bye, duck.”

Language Development

Awareness of sounds and cooing (1 to 4 months)

Very young babies react to sounds by blinking or widening eyes or turn toward a sound to look for its source. At about 3 months of age babies begin to respond with cooing sounds to someone who is talking with them. Talk with your baby so they can communicate with you using their sounds.

Repeating sounds (6 to 12 months)

At about 6 months, babies start to babble and repeat sounds, such as “ma-ma-ma,” to get attention or express feeling. As they get older, they learn to repeat more sounds and say simple words such as “mama” and “dada.” Encourage your baby to babble and make distinct sounds. Talk with your baby and teach them simple words.

Social/Emotional Development

Smiling (8 weeks)

The baby has an adorable grin, but the mom says, “That’s just gas.” Is she right? It depends on how old the baby is. An infant can’t produce what’s called a social smile until about 8 weeks. It takes that long for his nervous system and vision to develop enough to see you and produce a smile in response.

Smiling is a baby’s first social skill—he’s picking up on how relationships work—as well as a signal of emotional growth. A baby is showing you he can distinguish between different emotional states.

Hugging (5 months)

A baby will quickly learn to hug Mom, Dad and other people she’s comfortable around—as well as her stuffed gorilla, the cat, and anything else she adores—by watching others hug and getting hugged herself.

Not all babies are wild about hugging, though. Some are naturally more affectionate, while others are just too busy exploring their environment to stop for a cuddle. Try not to take it personally if the baby isn’t wrapping her arms around you. She might be more receptive to physical affection before naps, at bedtime, or while you’re looking at a book together.

All Babies are Different

Although no two babies go through these infant developmental milestones at the same time, babies tend follow the same progression through these milestones. There is a wide range of normal. Do not be tempted to compare your baby to others. Enjoy each stage and the fact that your baby is growing and changing each day. Boston Baby Nurse & Nanny provides parents with childcare services, support, and education.

Parents Guide to Developmental Milestones from the Child Mind Institute