Recovering alcoholic parent baby sitting

Long story short my mum has been an alcoholic most of my life, she’s “recovered” but relapses almost every month for a few days.

I’m now pregnant (after almost 7 years of trying) and we’ve built up a great relationship again, where I’ve finally felt I’d maybe trust her with my baby (something I never thought would happen). Today I saw her and she is baby siting my niece (10yo) and has relapsed again, she’s not awful but it’s obvious she’s had a drink. My dad is there (and sober) so my niece isn’t in danger but it’s just gave me so many doubts about the future.

Will I ever be able to trust her? Is it wrong of me to think I don’t ever want my parents to baby sit (is this taking away from my dad?) I feel so guilty for even thinking like this, but how could I leave my baby sit her not knowing if she’s going to drink or not 😞