My husband's 85 year-old father was diagnosed with Alzheimer's several years ago. He and my mother-in-law are in assisted living (she has cognitive impairment due to a stroke) but recently he has gone to the nurses crying that he wants to go see his parents and siblings (all are deceased). When he does this the nurses call my husband, who feels the responsibility to handle (read solve) every situation related to his parents. He is the eldest of three sons and is retired (the others are not). How can we help his father with this emotion, and therefore ourselves?
Call him by his first name. (If he is back in his childhood, he certainly will be confused by being called "Dad"). Tell him something that will make sense in his reality. "Your dad is out in the fields now, and your mom has gone into town. You'll see them later. While we are waiting, would you like to have some cookies and milk?" "Your brothers are all at school now. You weren't feeling very well this morning, and that is why you are staying in this nice place. Let's go down the hall and look at the lovely birds, so you can tell your brothers all about it later."
Tell him something comforting about why he can't visit with his relatives right now, and then distract him with something he might enjoy.
This is very, very hard on you and your husband, I'm sure. Hugs to you all.