My child was walking at 12 months but is now 18 months and having trouble walking. he's back to crawling. should i be worried?

What the evidence says

What you're describing, a child who could walk and now can't and has gone back to crawling, is called developmental regression. This means losing a skill your child already had and used regularly. It is different from the normal back-and-forth of learning, and different from a baby simply using crawling less as walking gets better, because here walking itself has been lost.

Medical guidelines say that losing a physical skill like walking, or losing strength, should be checked by a doctor promptly. This does not mean it's a dire emergency like a 911 call, but it does mean don't wait weeks to see if it fixes itself.

There are many possible reasons, and most are not scary. Sometimes a child is unwell, in pain from a minor injury, very tired, or going through a stressful change at home, and this temporarily affects walking. But regression can also point to something physical that needs treatment. In one published case, a toddler around 18 months old lost walking-related skills and it turned out to be caused by a bone condition called rickets, which is related to low vitamin D. Other causes doctors check for include muscle or nerve conditions, joint or bone pain, and general developmental conditions.

Because the list of possible causes is broad, the best next step is a visit to your child's doctor for a physical exam and a review of his overall development, not just walking. The doctor may check his muscle strength, joints, and reflexes, ask about diet, illness, or recent stress, and decide if any tests are needed.

Try not to panic. Many cases of regression have a simple, treatable explanation, and catching it early gives the best chance of a quick fix. But don't wait it out on your own, book that appointment soon.