Contributed by Cynthia Dedrick, Ph.D.
University of South Florida
| Gross Motor |
Mean age |
Normal Range |
| In prone
head up only |
1 month |
0 to
3 months |
| Head
steady at shoulder |
2 months |
1 to
4 months |
| In prone
head up to chest |
2 months |
1 to
4 months |
| In prone
head up to forearms |
3 months |
2 to
5 months |
| In prone
head up with extended arms |
4 months |
3 to
6 months |
| Rolling
front to back |
4 months |
3 to
6 months |
| Rolling
back to front |
5 months |
4 to
7 months |
| Sitting
with support |
5 months |
4 to
7 months |
| Sitting
independently |
6 months |
5 to
9 months |
| Creeping
on tummy |
7 months |
5 to
10 months |
| Crawling
hands and knees |
8 months |
6 to
11 months |
| Pulls
to a stand |
9 months |
6 to
12 months |
| Cruises |
11 months |
9 to
14 months |
| Walking |
12 months |
9 to
17 months |
| Running |
15 months |
13 to
20 months |
| Jump
on two feet |
24 months |
17 to
34 months |
| Kicks
Ball |
24 months |
18 to
30 months |
| Climbs
stairs with alternating feet |
30 months |
28 to
36 months |
| Peddles
tricycle |
36 months |
30 to
48 months |
| Fine Motor/Adaptive |
Mean |
Normal Range |
| Unfisted |
3 months |
0 to
4 months |
| Bats
at objects |
3 months |
2 to
5 months |
| Objects
to midline |
4 months |
3 to
6 months |
| Transfers
objects |
5 months |
4 to
7 months |
| Raking
grasp |
7 months |
5 to
10 months |
| Finger
feeds |
7 months |
5 to
10 months |
| Primitive
pincer |
8 months |
6 to
10 months |
| Neat
pincer |
9 months |
7 to
10 months |
| Voluntary
release |
12 months |
10 to
15 months |
| Helps
with dressing |
12 months |
10 to
16 months |
| Spoon
feeds |
15 months |
12 to
18 months |
| Uses
cup open/sippy |
15 months |
10 to
18 months |
| Imitates
housework |
18 months |
14 to
24 months |
| Handedness |
24 months |
18 to
30 months |
| Helps
with undressing |
24 months |
22 to
30 months |
| Undresses
self |
36 months |
30 to
40 months |
| Toilet
training |
|
24 to
36 months |
| Social/Emotional |
Mean |
Normal Range |
| Social
smile |
5-6
weeks |
1
to 3 months |
| Object
permanence |
9
months |
6
to 12 months |
| Stranger
anxiety |
9
months |
6
to 12 months |
| Affective
sharing |
10
months |
9
to 18 months |
| Uses
mother as secure base |
12
months |
9
to 18 months |
| Separation
distress |
12
months |
9
to 24 months |
| Independence |
18
months |
12
to 36 months |
| Parallel
play |
24
months |
12
to 30 months |
| Associative
play |
30
months |
24
to 48 months |
| Cooperative
play |
36
months |
24
to 48 months |
| Language |
Mean |
Normal Range |
| Cooing |
3
months |
1
to 4 months |
| Laugh |
4
months |
3
to 6 months |
| Turns
to voice |
4
months |
3
to 6 months |
| Razzing |
5
months |
4
to 8 months |
| Babbling |
6
months |
5
to 9 months |
| Dada/mama
non-specifically |
8
months |
6
to 10 months |
| Gesture
games |
9
months |
7
to 12 months |
| Understands
no, |
10
months |
9
to 18 months |
| Mama/dada
specifically |
10
months |
9
to 14 month |
| One
step command with a gesture |
12
months |
10
to 16 months |
| Immature
jargoning |
13
months |
10
to 18 months |
| One
step command w/out a gesture |
15
months |
12
to 20 months |
| Points
to body parts |
18
months |
12
to 24 months |
| Mature
jargoning |
18
months |
16
to 24 months |
| Puts
two words together |
24
months |
20
to 30 months |
| Pronouns
inappropriately |
24
months |
22
to 30 months |
| Two
step command |
24
months |
22
to 30 months |
| States
first name |
34
months |
30
to 40 months |
| Pronouns
appropriately |
36
months |
30
to 42 months |