Talk to Pediatrician on Dental And Hair Issues - 15 Yrs Old Boy

My son 15 has uneven and pale teeth, and 50% of his hair has turned grey. I dont know if both the issues are connected to each other, I mean maybe its malnutrition. Younger son 9 and daughter 5 show also similar symptoms, just not as worse as the elder. The daughter also has skin issues as she is having black layers on her neck. I am looking for relevant doctors in Attock or online. Need 2 or 3 opinions atleast.