Corrective medical sandals for boys with good arches.
Ankle supportive best sandals for boys from Europe. 
Leather orthopedic best ankle support for kids.
Pronation best high top sandals for boys with good arches.
Foot support best for flat feet in kids
High arches visible and present
Will not sweat either - despite open toes sandals feature none smelly soles
Ankle high with proper ankle support for pronation.
Best foot forming sandals that you can buy for your child.
They do not grab any sweat from feet but release to the air.
Buying quality shoes as those is investment in kids feet and posture.