Abbey
If your father in law is anything like my Mom's 3rd husband (the man I refer to as Dad although he's not my bio dad), then he is enjoying himself. My Dad divorced my Mom when I was 6. Yet he was always mowing the yard, planting a garden, trimming the hedges, raking leaves, and planting flowers. He planted a "garden" huge enough to feed Mom's 5 kids, his 7 grown kids and their children, his neighborhood, our neighborhood, various aunts and uncles, and still had enough left over to sell to restaurants and grocery stores.
He didn't have to do any of it. But he did clear up to (literally) the moment he died. Because he loved it.
Maybe father in law is just the old fashioned sort who loves to "take care of things".
And I'm sure I could boot one of my kids out so he could move in here.
husband gets any lazier about yard work and I just might boot him out too. ugh!!