4-5 months

• Shifts their weight over to one side to reach for a toy while on their tummy and up on their elbows
• Brings feet to mouth and puts hands on knees legs and feet while on their back
• Attempts to roll from their back to their tummy
• Starting to sit by themselves

6-7 months

• Pushes up on their hands while on their belly and/or rocks on their hands and knees
• Gets from on their belly to sitting
• Rolls from back to tummy
• Attempts to sit from laying down
• Sits and plays with toys with one hand support on the toy
• Commando crawls

8-9 months

• Transitions sitting in/out of hands and knees
• Pulls to stand with support
• Goes from laying down to sitting
• Sits independently reaching for toys
• Creeps on hands and knees

10-11 months

• Pulls to stand at an object
• Rotates and pivots while sitting to reach for toys
• Cruises at furniture
• Walks with one hand held

12 months

• Stands up without support
• Walks independently
• Lowers self with control from standing

13-15 months

• Stands for long periods without support
• Stoops to pick up an object from the floor
• Climbs into adult chairs
• Walks backwards a few steps
• Creeps up steps

15-18 months

• Carries object while walking
• Creeps down steps
• Attempts to kick
• Attempts to run

18-24 months

• Stands on one foot momentarily
• Steps over small barrier
• Walks up steps
• Attempts to jump
• Runs with more coordination