M.W.
I would say if maybe it was just an overnight trip then leave her with her grandparents, but 3 days is a long time to be separated from her. Has she ever been away from you overnight yet?
That said, my 1 year old has been going with us to Disney since she was 6 months old. I either have her in a baby bjorn or her stroller. And she hardly makes a peep all day. Bring a sarong or light blanket to put over the stroller at naptime. Or go back to the lodge for naptime. The great thing about staying on a Disney property is you can come and go as you please. Also bring a small soft sided cooler filled with snacks and drinks for the kids. And Pooh's Playground at MK is a wonderful place for you all to take a break. Let the kids run around [they have a little water area, so bring bathing suits if you want] and you can sit in the shade and have a rest too.
Have a great time!