—Not responding to their name by 12 months, or pointing to show interest by 14 months.
—Avoiding eye contact, wanting to play alone, not smiling when smiled at.
—Saying few words. Landa says between 18 and 26 months, kids should make short phrases like "my shoe" or "where's mommy," and should be adding to their vocabulary weekly.
—Not following simple multi-step commands.
—Not playing pretend.
—Behavioral problems such as flapping their hands or spinning in circles.
EDITOR's NOTE — Lauran Neergaard covers health and medical issues for The Associated Press in Washington.
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