I’d not say anything unless he says “mom look I didn’t drink”or wants to start conversations about drinking.

People don’t stop drinking because someone told them to. If he’s trying to stop because he came to that conclusion, it might not be a good idea to draw attention to it.

But it could also be that he didn’t stop drinking but just didn’t drink in front of you at the event. People with drinking problems get creative with hiding their drinking if they are tired to hear others talking about it. Then congratulating him is pointless, if that’s the case.

Have you tried Al Anon? As much as we wanted to, we cannot stop anyone from doing anything, especially when it comes to substance abuse.