Red Flags by Age: A Quick Reference Card

This card brings together warning signs in a short, printable summary. None of the signs described here means, on its own, that your child has an illness. But most of them mean that this condition should be evaluated by a specialist. Our aim is not to frighten you, but to help you notice the valuable clues right before your eyes. If you see a sign, rather than saying let's wait and see, share it with your physician; acting early is always safer.

The most important warning applies at every age

Of all the signs, the most important is regression, that is, the loss of a previously gained skill. This is an emergency at any age and must be evaluated without delay.

• Having started to talk, then losing words
• Being able to sit, then becoming unable to sit
• Having made eye contact, then stopping it, and ceasing to respond to smiles
• A walking child beginning to fall, and no longer being able to do things they did with their hands

General signs that apply at every age

The following should be evaluated carefully whatever the child's age.

• A marked difference between the two sides of the body, using one hand or leg far less than the other, a tendency to turn to one side
• Constantly using only one hand and ignoring the other during the first year of life, that is, a very early hand preference
• Marked stiffness and tension in the muscles, or excessive floppiness like a rag doll
• The head circumference being markedly much smaller or much larger than expected and changing rapidly

In the first months

• Movements being constantly one-sided, or one arm or leg moving markedly less
• The thumb constantly curled into the palm and the fist always kept closed, the hands not opening after the first months
• Giving no reaction at all to sound and light, not startling at all in response to a loud noise
• Marked difficulty in feeding, very weak sucking, constantly seeming to choke

Toward six months

• Not smiling in response to a face, not entering into back-and-forth vocal exchange
• Not turning toward sounds or your voice, remaining indifferent to noise
• Not reaching for objects, not trying to hold what is placed in the hand
• Marked difficulty holding the head upright even with support

Between nine and twelve months

• The complete absence, at twelve months, of gestures such as waving, saying bye-bye, and pointing
• The complete absence of babbling at twelve months
• Not turning when their name is called, remaining unresponsive when you call out to them
• Not making eye contact, being unable to sit without support, showing no inclination to explore

Between twelve and twenty-four months

• The absence of even a single meaningful word at eighteen months
• Not pointing to share interest at eighteen months
• Being unable to put two words together at twenty-four months, for example give water, come daddy
• Not understanding simple instructions, not entering into pretend play
• A marked delay in walking, persistent tiptoe walking, constantly leaning to one side

Points to watch in the social and emotional area

• The complete absence of the social smile and of back-and-forth exchange between six and nine months
• Not looking when you say their name, joint attention not being established
• Constantly and markedly avoiding eye contact, showing no interest at all in children their age
• Tantrums that last far too long for their age and cannot be soothed in any way, or states of shutting down and freezing