The words "developmental milestone" describe age-appropriate skills that a baby acquires during his early life. The University of Michigan Health System classifies milestones by function, including fine and gross motor skills, cognitive and social development and language. Milestones can also be classified by the age at which the average baby passes each milestone. Each baby is different, so learning skills at a particular age ranges widely. The March of Dimes suggests that parents who are concerned that a baby that cannot yet reach for toys, sit up unassisted or walk should speak to their child's pediatrician.
3-Month Milestones
The National Network for Child Care (NNCC) explains that parents should look for 3-month milestones when their baby is between 2 and 4 months of age; normal ranges for any milestone can span a month or more, especially in the case of premature birth. According to the NNCC, milestone for a 3-month-old baby should include his being able to lift his head and support his weight on his arms when he lies on his stomach. Holding toys or a parent's hand with an loosely opened fist is also developmentally appropriate at 3 months old, as is kicking his feet. Babies in this age group are usually able to track items with their eyes and respond to both visual and aural stimuli. Hand-to-eye coordination is another milestone for 3-month-old babies, states the March of Dimes. Communication beyond crying may come in at this age as well, in the form of cooing, gurgling and smiling.
6-Month Milestones
Six-month milestones, occurring around 5 to 7 months old, show an increase in steadiness with regard to motor skills. Babies of this age should be able to hold up their heads with little wobble. They should also be able to roll over; many can sit up on their own. Milestones for 6-month-old children include reaching out to grasp a toy and moving toys from one hand to the other, rather than just holding one when placed in their hand and playing with their feet and toes. The March of Dimes explains that cognitive milestones for this age group include a baby responding to her name, opening her mouth during feeding to anticipate a bottle, breast or spoon, laughing, and smiling at her own reflection. Communication milestones for the 6-month age bracket include full-on babbling, according to the NNCC. Some children may begin to crawl by the age of 6 months.
1-Year-Old Milestones
By the time they are a year old, many children make huge leaps in their development. Milestones marking the entry into toddlerhood include pulling up on pieces of furniture and walking with help. Some babies may even walk on their own before their first birthday. Fine motor skills include the baby using his thumb and index finger in a pincher grasp. Cognitive and social development is marked by the child's ability to wave "goodbye" when appropriate, respond to simple requests (or denials, such as when a parent says "no") and being able to identify objects by name in a picture. Language milestones for a 1-year old child include using the words "ma-ma" and "da-da" appropriately and trying to imitate speech.
18-Month Milestones
Eighteen months is a continuation of a baby's development and is marked with more advanced milestones. By 1 1/2 years old, most children who are not experiencing developmental delays can walk unassisted, according to the NNCC. Fine and gross motor development at this age include manipulating toys to make them go, such as in pushing and pulling, being able to look at a book and turn the pages, putting on and removing socks and hats and using crayons. Milestones for cognition at 18 months old include recognizing something silly or funny and laughing, following simple commands and using critical thinking to problem solve, such as when a child cannot find a toy, figuring out how and where to look for it. Language milestones include being able to say (and have others understand) about 10 words, saying "hi" and "bye" when appropriate and being able to ask questions using one to two words.
