it will be better to show on both of them, tell his dad to give an affidivate of support saying that he is the only and only son and he will be using my properties for his feature, and as per showing the bank balances tell them to keep a perfect proof of where he is getting that much of fundings, keeping the letters like chitfund companies and if he ishaving any properties like shopping complexes or so , then to take a letter from the rental shops that they are paying this much of amount like that.
If he is taking any loans, tell them to keep the documents from the bank who had given the loan, and u need to add all these items in u re CA letter.
What ever the income is comming if u are having the proof u need to take with u to the counsulate.