If your both parents line is ok then you may be having nutrition difficiency. Get properly assessed. Go for all types of fruits and raw vegetables.
Go for short duration High intensity Exercises with high whey protein diet.
Height or growth stops as soon as metaphysial plate in long bones gets mineralization. Difficult to find out. Simply go for boys games and gym with good nutrition.
More play more weight. Go for yoga too if psychological disturbance exist.
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