Some owners, indeed, worry because there is no rent day, they have no tenants, their houses are idle.
Others worry because their tenants are not to their liking, are destructive, careless, or neglect the flowers and the lawn, or allow the children to batter the furniture, walk in hob nails over the hardwood floors, or scratch the paint off the walls.

Men in high position worry lest their superiors are not as fully appreciative of their efforts as they should be, and they in turn worry their subordinates lest they forget that they are subordinate.
Mistresses worry about their maids, and maids about their mistresses.
Some of the former worry because they have to go into their kitchens, others because they are not allowed to go.

Some mistresses deliberately worry their servants, and others are worried because their servants insist upon doing the worrying.

Many a wife is worried because of her husband's typewriter, and many a typewriter is worried because her employer has a wife.

Some typewriters are worried because they are not made into wives, and many a one who is a wife wishes she were free again to become a typewriter.
Thousands of girls--many of them who ought yet to be wearing short dresses and playing with dolls--worry because they have no sweethearts, and equal thousands worry because they _do_ have them.
Many a lad worries because he has no "lassie," and many a one worries because he has.