Milestones in Infant Development

Milestones are behaviors that children and infants should exhibit by certain ages. Knowing the expected milestones at your baby's particular age can help you and your pediatrician assess whether your baby is developing typically. Infant milestones occur in how they play, learn, speak, behave, and move. The Centers for Disease Control describes developmental milestones at 2 months, 4 months, 6 months, 9 months and 12 months while the American Academy of Pediatrics groups infant development into 0 to 3 months, 4 to 7 months and 8 to 12 months 1.

Movement Milestones

Crawling and walking are not the only infant movement milestones. At 2 months, your baby should begin pushing herself up with her arms when placed on her tummy and holding her head up well. At 4 months, she should push down on her legs when her feet are put on a hard surface. She can also hold a toy and shake it and swing at dangling toys, bring her hands to her mouth and may be able to roll from her tummy to her back. At 6 months, she'll be able to roll over in both directions, she'll start sitting up unsupported, she may rock back and forth in a crawling position and she may start putting some weight on her legs when in a standing position. By 9 months, she should crawl, pull herself into a sitting position, pull herself into a standing position and stand while holding onto something. Around her first birthday, she may stand alone, or walk while holding onto furniture or even take a few steps by herself.

Social and Emotional Milestones

Just when the lack of sleep may really start getting to you, your 2 month old should smile at you. Your little one will also try to look at you when you are talking to her and really enjoy playing with you. At 4 months, she might cry when play time is over. She will also start trying to imitate facial expressions like smiles or frowns. By 6 months, she should recognize faces and have fun looking at herself in the mirror. She may particularly enjoy playing with her parents and be responsive to their emotions. With a 9 month old, expect a lot of favoritism. She will be clingy with preferred caregivers and afraid of strangers. She will have favorite toys as well. The favoritism continues as your little reaches the end of her infancy at 12 months. She will have favorite things and people and she may cry when they leave. Your 1 year old will also repeat sounds or actions to get attention, hand you a book so that you'll read her a story and enjoy games like "peek-a-boo".

Communication Milestones

Crying isn't the only way your infant communicates. Turning her head towards sounds and making cooing or gurgling sounds are other ways a 2 month old communicates. Two months later, those sounds will turn to babbling with expression. She will also cry in different ways to indicate whether she's tired, hungry or hurting. Your 6 month old will taking turns "talking" with you, even though her version of talking just includes vowel sounds and the occasional consonant like "m" or "g". She should also respond to her name and make different sounds to express happiness or displeasure. Pointing at desired objects is one of the key communication milestones for 9 month olds. Others include understanding "no" and copying the words and gestures of family members. Your 12 month old should be using a few simple words like "mama", "dada" or "no". She can respond to your simple requests and will try to say the words you say. She should also have more gestures, like waving good-bye and shaking her head.

Cognitive Milestones

In addition to learning how to move, connect and communicate, your baby will also learn how to think during her first year. Your 2 month old infant will start to follow things with her eyes and recognize people at a distance. At 4 months old she should use her hands and eyes together to reach for things she wants. Other 4 month old cognitive milestones include recognizing people and things at a distance, responding to affection, reaching with one hand and watching faces closely. Infants at 6 months start trying to get things that are out of reach, are able to pass things from one hand to the other and put things in their mouths. This is when baby-proofing really starts to pay off. A 9 month old will look for the toy you hide, use her thumb and index finger to put cereal in her mouth and should follow that path of something that falls. At 12 months, your little one will find the things you hide, look at the correct picture when an object is named, copy gestures and follow simple directions. She should also explore things in different ways, like shaking, banging and throwing her toys or her dinner.