Uptown Girls (2003) on Netflix

In New York City, Molly Gunn is a spoiled wealthy immature young woman, living as if she were a princess in a fairy tale. Her father was a popular rock-and-roll guitar player, who died in a plane crash with Molly's mother when she was a little girl. On her birthday in a nightclub, she meets Lorraine "Ray" Schleine, a nasty young girl with attitudes of an adult, living with her careless mother and a terminal father in a fancy uptown apartment. When Molly's accountant vanishes with her US$ 100,000,000.00 inheritance, Molly is left with nothing but debts, and she needs to work to survive without having previous experience or any skills. She is hired to be Ray's babysitter, and their close contact makes Molly reach the maturity and Ray act like as a child of her age.