I hope you have a calm weekend.
My AXH would hold off on drinking when his family was around (his family still thought he was a teetotaller when he went into rehab) -- but when we visited them, he'd be sober during family functions and then down a bottle of hard liquor as soon as we got back to the hotel (we always stayed in hotels, not with family, so that he could drink).
I second NewAugust in the caution that he might not be very pleasant if he's suffering withdrawals. I know that my XAH would literally be unable to sit still at family functions that didn't involve alcohol, and I knew that he was counting the minutes until he could pop a bottle open.