Child developmental Milestones Infants Eight to Twelve Months

GROWTH AND PHYSICAL CHARACTERISTICS

• gains in height are slower than during the previous months, averaging ½ inch per month
• infants reach 1½ times their birth length by their first birthday
• weight increases by approximately 1 pound per month
• birth weight nearly triples by 1 year of age
• infants weigh an average of 21 pounds
• heart rate averages 100 to 140 beats per minute, depending on activity
• respiration rates vary with activity, typically 20 to 45 breaths per minute
• body temperature ranges from 96.4 to 99.6 F (35.7- 37.5 C); still affected by environmental conditions: weather, activity, clothing
• head and chest circumferences remain equal
• continues to use abdominal muscles for breathing
• anterior fontanel begins to close
• approximately 4 upper and 4 lower incisors and 2 lower molars erupt
• arms and hands are more developed than feet and legs (cephalo-caudal development); hands appear large in proportion to other body parts
• legs may continue to appear bowed
• feet appear flat, as arch has not yet fully developed
• visual acuity is approximately 20/100
• both eyes working in unison (true binocular coordination)
• can see distant objects (15-20 feet away) and points at them

MOTOR DEVELOPMENT

• reaches with one hand leading in order to grasp an offered object or toy
• manipulates objects, transferring them from one hand to the other
• explores new objects by poking with one finger
• uses deliberate finger and thumb movement (pincer grasp) to pick up small objects, toys and finger foods
• stacks objects; also places objects inside one another
• releases objects or toys by dropping or throwing; cannot intentionally put an object down
• beginning to pull self to a standing position
• beginning to stand alone, leaning on furniture for support; moves around objects by side-stepping
• has good balance when sitting; can shift positions without falling
• creeps on hands and knees; crawls up and down the stairs
• walks with adult support, holding onto adult's hand; may begin to walk alone

PERCEPTUAL-COGNITIVE DEVELOPMENT

• watches people, objects and activities in the immediate environment
• shows awareness of distant objects (15 to 20 feet away) by pointing at them
• responds to hearing tests (voice localization) however loses interest quickly and therefore may be difficult to test informally
• follows simple instructions
• reaches for toys that are out of reach, but visible
• still takes everything to the mouth
• continues to drop first item when trying to take three offered items
• recognizes the reversal of an object
• imitates activities: hitting 2 blocks together, playing pat-a-cake
• drops toys intentionally and repeatedly; looks in direction of fallen object
• shows appropriate use of everyday items: pretends to drink from cup, puts on necklace, hugs doll, makes stuffed animal "walk"
• beginning to show an understanding of causality- hands mechanical toy to adult to have it rewound
• shows some awareness of the working relationship of objects: puts spoon in mouth, uses brush to comb hair
• searches for partially hidden toy by the end of this period

SPEECH AND LANGUAGE DEVELOPMENT

• babbles or jabbers deliberately to get a social interaction started; may shout to attract attention; listens, then shout again
• shakes head for no and may nod for yes
• responds by looking for voice when name is called
• babbling in sentence-like sequences; followed a bit later by jargon
• waves "bye-bye", clasps hands when asked
• says "da-da" and "ma-ma"
• imitates sounds that are similar to those the baby has already learned to make; will also imitate motor noises, tongue click, lip smacking, coughing
• enjoys rhymes and simple songs; vocalizes and dances to the music
• hands toy or object to an adult when appropriate gestures accompany the request

PERSONAL-SOCIAL DEVELOPMENT

• exhibits a definite fear or reluctance toward strangers; clings to, or hides behind parent or caregiver; resists separating from familiar adult (stranger anxiety)
• wants parent or caregiver to be in constant sight
• sociable and outgoing; enjoys being near, and included in daily activities of family members and caregiver
• enjoys novel experiences and opportunities to examine new objects
• shows need to be picked up and held by extending arms upward, crying or clinging to adult's legs
• begins to be assertive by resisting caregiver's requests; may kick, scream or throw self on the floor
• offers toys and objects to others
• often becomes attached to a favorite toy or blanket
• upon hearing own name, looks up and smiles at person who is speaking
• repeats behaviors that get attention; jabbers continuously
• carries out simple directions and requests; understands the meaning of "no"

DEVELOPMENTAL ALERTS

Check with a health care provider or early childhood specialist, if by first birthday, the child does not:

• blink when fast-moving objects approach the eye
• begin to cut teeth
• imitate simple sounds
• follow simple verbal requests: “come, bye bye”
• pull to stand
• transfer objects from hand to hand
• show anxiety towards strangers
• interact playfully with parents, caregivers, siblings
• feed self; hold own bottle or cup, pick up and eat finger foods
• creep or crawl