Before coming to any conclusions, we need to know his age , weight and height along with both parents height. We can comment only once the complete information is available If it genetic as you are suspecting then  supplements can be given but won't be of much use and use of growth hormones is not recommended until and unless leading to severe impairment.

I need to ask few more questions before answering your query. Early consultations can prevent complications. Kindly contact me on whatsapp chat (84960595 six five) Dr Faisal Zoheb MBBS , MD PAEDIATRICS , PGPN (BOSTON), FELLOWSHIP IN NEONATOLOGY ( Newborn and vaccination specialist )

Before commenting on this issue physical evaluation of your son is needed

Visit physically to nearby pediatrician

Consult with Pediatrician physically for further evaluation and treatment

Good afternoon, Tell his age, height and weight, with parents height. So that the physiological things can be ruled out before considering anything

At present what's the age and height? Needs to check evaluate Bone age index