Fines are criminal liabilities, not civil liabilities. Does not affect the commutation.
Moreover, if the offender is an adult, then his family members are not obliged to bear the liability for compensation for the fine. Unless their family members or friends voluntarily pay this fee, the court can't make a compulsory request.
If this part of the fine is in arrears, the criminal must pay the fine first as long as he has personal property.
To be clear, fines are criminal penalties, not court fees. There is no need to pay legal fees for the trial of criminal cases.
I hope it's been explained clearly.