I don't think it's a big deal quite honestly. Their parents had no such qualms relinquishing those duties whenever they could. We get to grips with all of that as a parent, there's something quite satisfying in making ay baby feel clean and fresh again. Being in charge as a grandparent reminds you, unlike when you were a parent, this comes to end a whole lot sooner. I'm not always so keen on the grandparent duties to the granddog, as lovely as he is, It's the little bags [yuk] having been a parent to cats previously at least they had the grace to clear up after themselves.