Am I Entitled to a Refund of Retainer

My question relates to legal practice in the state of: california

My son retained a family law attorney for an upcoming court date.
He paid 2500 retainer. The attorney said he would appear in court for my son on the date.
I assume he would, that's why he hired him, for legal representation, especially in court.
Anyway, I check the minutes for the date, and it indicated that his wife's attorney was present but my son's attorney was not.
Does my son have recourse to ask for his retainer to refunded or returned based on the attorney's negligence etc?, and if attorney refuses to take it up with the calif bar association as a complaint?

Thanks

Am I Entitled to a Refund of Retainer