My Mother's Car — Janice Daugharty

Ten year old Doodle is in charge of his little brother and baby sister for the summer while his mother, Nina, is awaiting the arrival of her fourth baby. Nina claims that her husband's bossman's wife gave her a Mercedes, which Noodle knows will either have to go back or be paid for. They have no money so Doodle tries to keep the car clean, but his sister and brother make a playhouse of it.