Moreover, it's not necessary to force everyone in the same house. My parents and inlaws are within 20 minutes. It's great and since they are both married and happy, there's little family stress and the kids get ample time with both grandparents. God forbid, if anything were to happen to either my wife or I, they would be well taken care of.
Eventually our parents may move in or closer by, but right now, it's nice for everyone to have some separation.