Leaving child with grandparents that drink

DH and I are going on a beach vacation in a couple of months and will be leaving our recently turned 4 year old for a week. We had planned to leave her with grandparents and present it as a special treat for her. She has stayed a handful of overnights with them each year since she was 1 and we see them often. We have no concerns with her being comfortable and behaving for them. She adores them and they her. We also have backup sitters in the event of illness or just plain exhaustion and someone needing a break. Our new found concern is the amount grandparents drink. They've always been beer drinkers and plenty of time to excess. But not while keeping the kiddo. When she was tiny we asked them to refrain while babysitting because with them there's no such thing as a beer or two; if they have two they're continuing and having 10 or more each evening. Recently Grandma admitted that she is addicted to her nightly beers. She stated that weekends grandpa is on call for work and they can't drink that she'll stick with just two or three because if she doesn't then she can't sleep. She brought this up herself and volunteered the info completely unprovoked. After a few beers, of course. I'm not completely convinced she would have told me had she not already been drinking as she tries to brush off how much they drink lately.We are both worried about leaving kiddo with them for a whole week now, and aren't sure it's in her best interest. Actually, we both admit that it isn't and that it would be neglectful of us seeing as we don't trust them to not have several beers each night even if they agree that more than a couple is too many while babysitting.I'm not sure what I'm looking for. We have other options for sitters and while we'd rather not hurt grandmommy's feelings and piss her off our child's well-being is our first priority. I feel guilty relying on our backup to become our primary and I know it will cause more stress for the little one since she will be out of school for the week if she stays with our backup. She'll also be spending the week with her two best friends which she'd love but the serious change in routine will throw her off in a major way. I'm just not sure that the risk of staying with drunk grandparents could ever outweigh the chaos of staying with her friends and missing preschool and basically have a week long play date with her favorite friends. via /r/Parenting http://ift.tt/2a9DxwH