There are people who are trying to fill that need from gardening, to reading, to playing the piano.
They're part of an important weekly ritual for Nan Carey and the Fryett-Tigges family.
Jessica Fryett-Tigges is from England and her husband's from Brazil.
They have three children under five - Lais, and identical twins Chloe and Saskia.
Neither has extended family in Australia, prompting them to join a not-for-profit group which links families with surrogate grandparents - in this case with a woman they have come to call Nan Carey.
"For my husband's mother she's never seen them at all, because she has had to look after her mother in Brazil and she hasn't been able to travel. For my parents they come out annually, if they can. And I have been back to the UK once to see my parents with Lais, but as soon as the twins came it's been harder."
Ms Fryett-Tigges says she was concerned her children were missing the influence of an older person in their lives and decided she should ensure her kids had that influence.
"Fostering those relationships with an older person and seeing those ethics and values come through from that generation, which I think is missed in my peer group or the younger generation."
The benefits go both ways.
Now retired, former librarian Nan Carey is an active member of the community and enjoys sharing her love of gardening, music and reading with others. But moving to a coastal town with a large retiree community and away from her own immediate family made her miss the company of younger people.
Volunteering to be involved in the life of a young family has helped her stay connected.
"It keeps me in touch with younger people. I don't have a lot of contact with younger people, so you miss out on that and you just feel like you're moving around in one circle of your age group. And it's lovely to get that variety again and feel like you're more part of life. And I enjoy it because I love all the things that young people like to do."
Find a Grandparent founder Cate Kloos set up the website six years ago.
It was not only for migrants but for anyone without grandchildren or grandparents due to many factors, including distance or family breakdown.
Her initial motivation, though, was to find a surrogate grandparent for her own children after migrating from Germany.
She eventually found a woman in the local area who still has regular weekly contact with her family.
"I think I pretty much set it up out of desperation. So my family in Australia, we don't have any wider family around. So no grandparents for my children. I thought that was really sad. I was very close to my grandma when I was growing up and I wanted to give my kids the same experience. But then I thought that a lot of families would be in the same situation like me and they will benefit from it and older people would benefit from it as well."
Demographers say the effects of a more mobile world population are also being felt by older people left at home. Populations around the world are aging, resulting in an increasing need for long-term care.
In countries where government social support systems are insufficient, care often falls to families and adult children are often expected to care for their relatives.
Dr Liz Allen is a demographer at the Australian National University in Canberra.
"Certainly this is something that we are seeing worldwide, that kind of inter-generational relationship are interrupted. So think from a parent perspective or a grand parent their reliance on that network for their children or grandchildren to care for them as they are is disrupted. Now that means that different financial supports and social supports that are needed in those countries for elderly parents, they struggle to cope with looking after themselves. And for countries that have a long history of families caring for their elderly it's a big problem."
She says countries such as China and Japan are being forced to find new and creative ways of adapting to their rapidly aging populations.
"So there are facilities much like a youth centre that becomes an aged centre where people can go and participate in yoga and exercise that is suited for the elderly. So we are seeing some very smart ways of coping with this change in family and migration patterns."
Jessica Fryett-Tigges says she understands many have safety concerns about allowing strangers into their families.
She encourages isolated families to choose programs that require all volunteers to complete police checks, including working with children checks.
Beyond that, she insists parents should also spend some time with volunteers to see if they are a good match in terms of values and interests.
"Obviously the first meeting is non-obligational to see if there is a click (some compatibility) and you can usually use your maternal instinct and the relationship will develop over time. You'll know if it's right."
Nan Carey says many adults need to remember how to have fun.
''Children make you feel young. I enjoy that. You play and we don't play as we get older and it's lovely to play."
