Ok cut a long story short, my MIL has been staying for the last 3 nites as FIL in hospital down the road from us. MIL background - we've always got on well, quite hands on with the kids altho lives quite far from us. She's always liked a drink, I've seen her sloshed on several occasions, can be argumentative, has had a pop at me before when pissed.
First nite she came back from the hosp, had clearly had a drink on the way home as smelt of alcohol. Fair enough I thought, stressful day, caught in traffic etc (her), had bought a bottle of wine with her which we shared, me MIL and DP.
Second nite she came back, seemed ok, didnt smell of booze. Disappeared to her room then came to help me bath DP at which point I smelt booze on her breath. Odd i thought as although she had bought a bottle of wine home with her it at this point was unopenned. She later openned and drank some/most of it. Later when I went to her room to get something I 'accidentally' noticed a bottle of sainsbury's vodka almost empty, stashed in her bag.
Third nite, the same again and this time I actively went looking for the vodka (hoping that this was a one off i spose) and found the bottle had been replaced - this time a cheap russian brand from a local offie. Not much drunk but I secretly monitored the level over the course of the evening and it went down a few inchs. In the meantime we had a bbq and she drunk some wine, I didnt join her, didnt really feel like it.
Now I dont know what to do. Of course i feel bad for looking in her bag but kind of feel that if she is going to look after my kids now and then i'd like to know if she has a problem - well tbh I always knew she had a 'problem' (social wine drinking something I myself enjoy) but stashing alcohol and taking sneaky swigs kind of takes it to another level in my eyes. I havent told DP yet as thought he may fly off the handle and be angry with his mum who then would be angry with me etc and none of us needed that with FIL not well. I spose I need to tell him, although I am hoping this is just a one off - stressful situation with FIL etc.
More a WWYD I spose than an AIBU but all advice gratefully recieved.