While your underage son is in your home, you can certainly require him to go to Mass with you, but you cannot require him to receive Holy Communion. Unless he expresses a desire and is properly disposed to receive (if a person is conscious of a grave sin, confession is required before going to Communion), he should refrain from receiving the Eucharist.
St. Paul warns about receiving Communion in an unworthy manner:
Whoever, therefore, eats the bread or drinks the cup of the Lord in an unworthy manner will be guilty of profaning the body and blood of the Lord. Let a man examine himself, and so eat of the bread and drink of the cup. For anyone who eats and drinks without discerning the body eats and drinks judgment upon himself. (1 Cor 11:27-29)
Your priest can give you proper counsel about this problem.