With my daughter's provider she'd invite me over and tell me Come over in the morning when you're ready - have coffee, we'll do lunch with the kids then you can leave for her nap.

We're good friends now and recently she had a mom of two boys come and do the same (2-3hrs) once every week or two weeks....for about 2 months - mom is a teacher and was off all summer plus the little one is a clinger! It seems to work for her but not all day!