Flat feet is a term for feet which press flat on the ground.
Before the age of 3, all children have flat feet. The arch on the inside of the foot develops later.
Also in this section
If your child has a problem which does not improve as you would expect with self-care, you should contact a healthcare professional for advice. This may be your GP, Pharmacist, NHS Podiatry Service or a Private Podiatrist.
Please make sure your podiatrist is registered with the Health and Care Professions Council and look out for the letters HCPC after their name.