In many parts of the world it is the norm to have three, sometimes even four, generations of a family living together under the same roof.
But in the UK and many other countries in Western Europe, it is far more unusual. In fact, it is a domestic arrangement more likely to be found in a TV sitcom than in most people's real lives. But all that could be changing.
A combination of economic necessity, demographic changes and increased multiculturalism is predicted to see a big increase in multi-generational living in the UK over the next decade and beyond.
According to research by insurance company Aviva, a million more young people are likely to find themselves living with their parents by 2025. The study predicts that 3.8 million people aged between 21 and 34 will be still living with their parents by then, and by no means all of them will be single.
The number of households containing two or more families is predicted to rise from 1.5 million to 2.2 million. The main motivation is an economic one, with Aviva's study assuming that house prices will continue to rise at the same rate as they have over the past decade, making them unaffordable to many young people and families.
For some young couples the idea of living in one of their parents' homes is a nightmare, but according to the research, many who have been forced into it actually find it can be a very positive experience, with many practical advantages.
First and most obviously, it can remove a huge financial burden, with shared living costs allowing young families more expendable income and the opportunity to save. Meanwhile their parents can benefit from additional income in the form of 'rent', or just help with the household bills.
In homes with three generations there are even more advantages, with grandparents on hand to help out with free childcare, and often glad of the opportunity to spend more time with their grandchildren. Conversely, the older generation can benefit from more help with household chores and informal care if they become ill or frail.
Just having people around for company can be a major social benefit, especially for grandparents who have been bereaved and could otherwise find themselves living alone and feeling isolated.
Of course, a lot depends on the individual circumstances. Multi-generational living works best in larger houses, where the inhabitants can have their own living space as well as enjoying shared spaces when they choose to. In overcrowded accommodation, arrangements can be more fraught!
Yet in many societies, the idea of family generations living apart is just as bizarre. Extended families living together, sharing costs and caring for each other is the natural way. In these societies the notion of working all hours to pay bills for another home, paying for childcare by strangers or putting elderly parents into residential care homes is absurd. That is what families are for.
So who has it right? Maybe the ever-rising cost of increasingly unaffordable property will lead families in the UK to rediscover a different way of family life.