Hello Shekhar Thank you for placing your query on Health Care Magic I can understand your problem. MCDK is a condition in which kidney has not developed fully and hence does not function at all. But children do well on one kidney for entire lives. So you need not worry about it. Only thing is to take care of is the other single kidney. MCDK usually get absorbed in the body and hence we just need to keep evaluating with ultrasounds, confirming that it is decreasing in size. By the age of 5 years or so it should completely disappear. However, if its very large to begin with (size greater than 6 cm), not reducing in size or causing any symptoms to the baby or your baby develops hypertension, then it should be removed. It is a very minor surgery and nothing to worry about. As for the other kidney, try to avoid contact sports. Any disease in this kidney should be promptly treated. If the size of the stones is small and not causing any obstruction (a DTPA scan will tell), then we can wait for these stones to pass. However if the stones are causing any obstruction we should tend to get them removed. Other important factor here is to know why your son has developed stones at this young age. Consult a pediatric surgeon and he should be able to help you with these issues. Hope that solves your query God bless you