I can talk about this topic first hand. I have three gorgeous kids who have all lived at home well into their twenties, even thirty!

What a Ride
We used to live in the idyllic mountains on 5 acres, a glorious place to bring up teenagers. You know, the bushland terrain, possums, goats, a horse, quaint villages and wonderful birdlife …...everything that a growing teenager desires!!!!!!
They grew up and moved back into the city! The kids shifted into an inner city semi detached house together and lived probably less than harmoniously for about three years.
In the meantime my husband and I decided to downsize, the amount of work to keep this bushland residence in good order for the two of us seemed generally a waste of time. So we packed up with a view to changing our ‘lifestyle’. It was the peak time real estate wise in Sydney and getting something, anything in your price range was almost impossible. We eventually found our house. It is a small single front house close to the City but it came with a second story which allowed independent living upstairs.
The kid’s cries came thick and fast - “Can we come and live there?”
Of course we said ‘yes’ and really, I think it has been the making of our family and how everyone gets on together.
Over the years the kids have come and gone. While The Doh lived there, The Pot was living in Melbourne and The Bride was living in England. The Doh moved out when he married Sweetie and then when The Pot came back to Sydney. The Pot got engaged and bought a house with Beautiful and moved out. Now The Bride has moved back from the UK. There was some overlapping but the whole experience for us, and hopefully them, has been absolutely wonderful.
You know, you really don’t grow together with your kids as adults especially in those strange years between the ages of 16 to 22. Then, because our kids had physically separated from us and were living independently for a long time they came back to the as house fully fledged adults. They did their own washing, ironing, cleaning and we shared the cooking and we all looked at each other in a fresh way. The bonding that has happened in this house has been rewarding. I like to believe we have wonderful relationships with our kids because of this arrangement. And the relationship between the kids themselves has grown and developed into a real appreciation of each other which may not have been possible under a different framework.
So, I guess we could say we are lucky in this otherwise problematic situation. Our kids are well adjusted, well employed and happy individuals so the situation has worked.
Mr G and I never feel like our life has never been impinged upon and our friendship with all our offspring and their partners is a joy.