I know how you are feeling. When I went to Florida in april I had the hubby stay home with all ours. I really didn't think he wanted to go see the in-laws. but when he goes 4-wheeling for the weekend I have to stay home
I really would like to go but have no one to watch them
It is hard but i think you should let your friend watch them.Just be sure to ask her to not let the kids be alone with them for both their safety.
Good luck and don't worry they'll be just fine.