At 9 months, a typical infant will demonstrate certain skills and growth markers known as milestones.

PHYSICAL CHARACTERISTICS AND MOTOR SKILLS

A 9-month-old generally has reached the following milestones:

• Gains weight at a slower rate -- approximately 15 grams per day, 1 pound per month
• Increases in length by 1.5 centimeters per month
• Becomes more regulated in bowel and bladder systems
• Shows parachute reflex to protect self from falling
• Is able to crawl
• Remains sitting for prolonged periods
• Pulls self to standing position
• Begins preference for dominant hand
• Has a pincer grasp between thumb and index finger

SENSORY AND COGNITIVE SKILLS

The 9-month-old typically:

• Is developing depth perception
• Achieves "object constancy", the understanding that objects continue to exist even when not seen
• Responds to simple commands
• Understands the meaning of "no"
• Imitates speech sounds
• May be afraid of being left alone

PLAY

To aid the development of the 9-month-old:

• Provide picture books
• Provide different stimuli:
  • Go to the mall (people)
  • Go to the zoo (animals)
• Play ball
• Build vocabulary by reading and naming people and objects in the environment
• Teach hot and cold through play
• Provide large toys that can be pushed to encourage walking