If I Were You by Alan Ayckbourn

Jill and Mal Rodale seem to have lost the spark in their marriage. Their son, Sam, resents his father and and their daughter, Chrissie, has recently had a baby and is dealing with marriage issues of her own. They share advice, but no one is listening till one morning Jill and Mal wake to find they have taken on each others personalities. Their families are not aware of this change and they must carry on "as normal". Will seeing things from the other's point of view make things worse or will this be just the thing to save their family?