Such problems can managed by any orthopaedic. You will have to give few details as in what is the problems kids are having with the flat foot in current lifestyle so management can be done according to the same
Next Steps
Kindly show it to a orthopedic in person or atleast video consultation so that they can see and recommend the right treatment
Health Tips
There's nothing much to worry as a lot of people with flat foot lead a normal lifestyle after the right treatment