A: It sounds like your son is having a hard time with teething. At 21 months old, he may be getting his canine teeth or his second (“2-year”) molars, which are bigger and can be more painful when they cut through the gums. Discomfort, low-grade fever and loss of appetite are common.

Hopefully, your son will be over most of the discomfort in a week or so. Since your son is almost 2 and has otherwise been healthy and growing well, his body should have enough fat stores and nutritional reserves so that a week of eating less should not be harmful. You don’t need to force him to eat if he’s not hungry. You can gently encourage him by offering him little nutritious snacks and fluids (e.g., milk, juice and water) throughout the day. When the worst of the teething is over, in a week or two, his appetite will come back and he’ll make up for what he missed.

Some parents find that giving their teething toddlers chilled foods to chew on (e.g., chilled apple slices and frozen waffles or bagels) helps relieve the gum discomfort. Pain medication such as acetaminophen or ibuprofen may also help—consult your doctor about the right dose. (Never give your child aspirin.) Some doctors recommend rubbing an over-the-counter anesthetic ointment on the teething gums to numb the pain right before eating, but you should use it sparingly.

There’s also a chance that your child’s low-grade fever and loss of appetite may be due to an illness such as an ear infection or the stomach flu. If he gets sicker with a higher fever, ear pain, vomiting or diarrhea, be sure to contact the doctor.