Things go bump in the night when you are the only human in the household.
Christmas ornaments only go on the top half of the tree.
The lint trap is primarily full of fur.
There's a cage on your deck (aka a catio) and it happened to be the first project you did when you bought your new house.
There are empty boxes throughout the house.
The Christmas tree skirt is no longer under the tree.
The Christmas tree isn't the only tree in the house.