(HealthDay News) -- While most cases of the common cold in young children are harmless, there are certain warning signs that should prompt a call to the pediatrician.

The American Academy of Pediatrics offers this list of "red flags" among children 3 months or older:

• Nostrils that spread with each breath, difficulty breathing, or the skin near the ribs "sucks in" when the child breaths.
• A blue tinge to the nails or lips.
• Nasal mucus that doesn't go away after 10 to 14 days.
• Persistent cough that lasts for longer than a week.
• Ear pain.
• Unusual sleepiness or crankiness.
• A temperature higher than 102 degrees Fahrenheit (38.9 degrees Celsius).