When are you grown up? In prior generations, young adults were expected to have finished school, paid for school, found a job, and set up their own household during their twenties--most likely with a spouse and a child included in the mix. More Americans 18 to 34 today live with their parents than with a spouse. There are now more young people living with their parents than in any other arrangement. 22.9 million 18 to 34 year olds are living today with mommy and daddy. 19.9 million are married and live with their spouse.