Scary symptom: Your child is doubled over with stomach pain.
You think: It's appendicitis!
It's probably just: A stomach bug, especially if she has diarrhea and a fever. Don't reach for over-the-counter upset-stomach remedies -- some contain an aspirin-like compound that can lead to a dangerous condition called Reye's syndrome in children. Just help your child feel more comfortable: Place a heating pad on a low setting on her belly and give her an ounce or two of clear liquid every 10 or 15 minutes to keep her hydrated.
When to worry: It may be appendicitis if she has crampy stomach pain that starts around the belly button and worsens as it moves to the lower right side of her abdomen. She may also have a fever and might vomit -- but she won't have diarrhea or any bowel movements, due to swelling in the bowel area. "One of the best ways to tell whether it's appendicitis is to ask your child to jump up and down," says Ari Brown, MD, Parents advisor and coauthor of Toddler 411. "A child with an inflamed appendix can't do it because it hurts too much." Appendicitis requires immediate attention, so go to the ER right away.
Scary symptom: Your toddler hasn't pooped in days, and her belly looks swollen.
You think: She has a bowel obstruction -- people die from that!
It's probably just: Plain old constipation. "When your child's bowels don't move, her intestines can fill with poop, which will make her belly look bloated," explains Dr. Brown. Constipation is a common issue for toddlers -- it often occurs when a child is switching from formula or breast milk to cow's milk and when she's potty training (lots of kids are scared of using a toilet and hold it, which could make it more painful and difficult to poop later).
Your constipated kid may also pass gas and refuse to eat. The fix? Give her more fruit (even a couple of ounces of prune or apple juice a day may do the trick), vegetables, fluids, and whole grains. If she hasn't pooped in a week or so, call your pediatrician. "Ask if using oral stool softeners or laxatives along with plenty of fiber and water will work," says Dr. Brown.
When to worry: If your child has a distended and extremely tender belly, hasn't pooped in days, or passes stool that looks black and jellylike and is also vomiting, you should head to the ER immediately. These are signs of a bowel obstruction, which occurs when the intestine becomes twisted. She may need emergency surgery.