Tell grumpy husband he can be grumpy on his own, you will be away for more than the week - long enough to make the long journey worthwhile and really see your family. Add that he sees plenty of you the rest of the time, and he will enjoy having you back all he more for being without you for a while. It will be like another honeymoon!
Tell daughter that three days is nowhere near long enough, as after the journey you will take at least a day to recover - and so will she and the baby - and then you both will have to pack up and come home. She hasn't yet discovered just how arduous it is to travel with a baby.
Suggest that she either comes for the one or two weeks, giving yourselves time to relax after the journey and time to see the family, or that you go alone this time and she takes the baby on a future trip (when, incidentally, it will be even more arduous, because baby will need to be entertained while travelling!)
Her husband is just as competent to be left for a couple of weeks as yours is. They could even get together and share the chores (and the grumbling!)