Milestones: Red Flags to Watch For

Birth to 4 months

Babies change and grow a lot during their first few months of life. The average newborn gains 5 to 7 ounces a week. They also grow 1/2 inch to 1 inch each month. In short, your baby is getting bigger before your eyes. They are also developing new skills. But if your little one has trouble with any of the following, it could be a sign that something is wrong:

• While babies may cross their eyes often in the first month or two, flag with your pediatrician if your baby has trouble moving their eyes or is crossing them most of the time
• Doesn't respond to loud noises
• Doesn't notice own hands (by 2 months)
• Doesn't follow moving objects with eyes (by 3 months)
• Doesn't grasp objects (by 3 months)
• Doesn't smile at people (by 3 months)
• Can't support head (by 3 months)
• Doesn't babble or try to imitate sounds (by 4 months)
• Doesn't bring objects to mouth (by 4 months)
• Doesn't push down with legs when feet are on firm surface (by 4 months)

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By 7 Months

As your baby continues to grow, so too will their skills. Many 5-, 6-, and 7-month-olds roll, smile, and laugh. They grab toys frequently—and put objects in their mouth—and they babble and squeal. Their world expands each and every day. And while your baby may not have hit all of these milestones, at least not yet, the following could be a sign something is amiss:

• Seems very stiff, with tight muscles
• Seems very floppy, like a rag doll
• Head still flops back when body is pulled to a sitting position
• Reaches with only one hand
• Refuses to cuddle
• Shows no affection for the person who cares for him
• Persistent tearing, eye drainage, or sensitivity to light
• Difficulty getting objects to mouth
• Doesn't roll over in either direction (by 5 months)
• Can't sit with help (by 6 months)
• Doesn't laugh or make squealing sounds (by 6 months)

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By 1 Year

By your child's first birthday, they've probably changed a lot—physically, mentally, socially, and emotionally. Developmental milestones are things most (75 percent) of children can do by a certain age. But if you have any concerns and/or if your child is exhibiting any of the following behaviors, you may want to speak to their pediatrician:

• Doesn't crawl or scoot, or drags one side of body while crawling
• Can't stand when supported
• Doesn't search for objects that they see being hidden
• Doesn't say mama or dada—or any other single words
• Doesn't use gestures, such as shaking head "no"
• Doesn't point to objects or pictures
• Can't walk (by 18 months)
• Doesn't walk heel-toe within a few months of walking

RELATED: Baby Talking Timeline: A Month-By-Month Guide to Speech Development

By 2 Years

Ah, toddlerhood. There's nothing quite like it. Most 2-year-olds crawl, walk, and talk. They are also balls of energy—running, jumping, and simply going 100 miles a minute. But if your child is struggling physically, socially, or emotionally, you may want to speak to an early intervention expert. These are some signs that something could be wrong:

• Doesn't speak at least 15 words
• Doesn't use two-word sentences
• Doesn't imitate actions or words
• Doesn't follow simple instructions
• Can't push a wheeled toy

RELATED: The CDC Updated Their Developmental Milestones for Kids—Here's What Parents Need to Know

By 3 Years

Can you believe your baby is 3? Thirty-six months have passed since your wee one was born. But if your toddler is having difficulty with any of these things, you may want to speak with their doctor and/or pediatrician:

• Frequently falls or has difficulty with stairs
• Drools persistently or speaks unclearly
• Can't build a tower of more than four blocks
• Has trouble manipulating small objects
• Can't copy a circle
• Can't communicate in short phrases
• Doesn't engage in pretend play
• Doesn't understand simple instructions
• Shows no interest in other children
• Makes poor eye contact
• Has little interest in toys

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Concerned About Your Child's Development?

You know your child best. If something seems off or "wrong," don't wait, speak up, and get help. "If your child is not meeting one or more milestones, has lost skills he or she once had, or you have other concerns, act early," the CDC explains. "Talk with your child's doctor, share your concerns, and ask about developmental screening."

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