Blended family here. My 2 daughters were out of the house by age 20.
My Wifes daughter is still with us at 27. After a long "debate" with my wife of what we should start expecting from her, we finally started charging $400 rent when she stopped going to school.
We did make her go and buy her own phone, car, and insurance at 23 after she fell off our health insurance.
She has a boyfriend that is over all the time. Nice kid but dragging his feet on commitments. (hey I know how the "why buy the cow when...." goes)
We get along great but I cannot understand the lack of desire to get out on their own together.
Rent and houses are expensive, and we do not mind giving them a little time to figure it out. But come on!!!
If I could get a great paying job in Alabama I would rent this house to them, and the wife and I would go live down on lake G.