It’s always good to let children know when you are going away for whatever reason. However, just tell them no more than 1-2 days before the departure as children’s concept of time is different than ours. When our children were young and i went away for a longer time, i made a Mommy tape. For each child there was something.For example, for the older one that had a hard time waking in the morning i put on different versions of Modeh Ani.For the younger ones there was the usual morning routine with a Good Morning, “did you remember to was negel vaser” and for the night a story with Krias Shema. It ended up being so helpful that the young one would listen to the tape even upon my return and i watched as he responded non verbally to my questions on tape with nodding. Another suggestion is to make a calendar with only the amount of days you will be leaving for, beginning with the day you leave. So for example if you are leaving from Sunday thru Sunday, you will make a calendar of 8 boxes. You will sit with the child(ren) and show, “today is Sunday and we are leaving today, so mark with an “X”. Then tell them to make an “X” on one box each day and the day that they mark with the last “X” is the day Daddy/Totty/Aba and Mommy/Ima will be here to take us all home.This works for even if one parent will be going away.
Another suggestion is not to talk to them via phone when you are away. With the younger ones especially it creates issues as crying for parent(s).
Enjoy your trip/vacation!
Oh, i forgot to add, it’s best not to leave children with total strangers even if you pay them!