Cousins are disappearing. Is this reshaping the experience of childhood?

Noelene Lancastle grew up surrounded by 27 cousins and 10 second cousins. They were a range of ages and had what seemed like a world of experiences, always ready to teach her to skateboard or swim, help carry heavy boxes, play with her on camping trips or have her back in school in North Delta, B.C.

"There were always lots of kids around. You know how your parents dragged you around to houses? There were always some kids for us to play with that were somehow related to us," Lancastle, 46, said from Vancouver.

It's something her own children won't experience.

Lancastle's older brother and sister don't have children and her husband is an only child. So Nicholas, 9, and Charlie, 7, don't have any cousins at all — a growing trend as the decreasing fertility rate causes extended families to narrow over time, sociologists and demographers say.

Worldwide, families are shrinking, according to a kinship study published in December in the Proceedings of the National Academy of Sciences USA. That study, using international demographic data for every country in the world, projected a 38 per cent global decline in living relatives for individuals aged 65 by the year 2095, compared to 1950.

The composition of family networks is also expected to change, with grandparents and great-grandparents living longer, but the number of cousins, nieces and nephews declining, the authors noted.

"Canadian children nowadays have fewer cousins than previous generations," said Rania Tfaily, an associate professor in sociology at Carleton University in Ottawa who studies social demography and contemporary changes in marriage and family formation.

This isn't a recent phenomena as fertility rates have been decreasing for some time, added Tfaily, who was not involved in the kinship study.

"However, what is striking nowadays is not just that the number of cousins is declining but also that an increasing number of children are growing up with no or very few cousins."

And it's part of the reason Lancastle decided to have two children, despite having them later in life.

"I could have been a one and done person," she said. "But they would have no relatives that would be their age. So I wanted them to have each other, at least."

Families are shrinking

Canadian data obtained by CBC News from the researchers of the kinship study projects that the average Canadian 15-year-old girl will have just 3.6 living cousins in the year 2095, compared to 15.3 in 1950 — a 76 per cent decrease in living cousins.

Using demographic data, the researchers computed kinship structures for every country in the world from 1950 to present, and then calculated projections to the year 2100. The model is based on a hypothetical person from the population, in this case, a woman of a specified age.

A Canadian woman aged 35 would have had about 20 living cousins in 1950, while a woman the same age would have half that — 10 living cousins — in 2020. By 2095, a Canadian woman aged 35 is projected to have just five living cousins, according to the data.

This narrowing of extended families tends not to get as much attention as research on the nuclear family, the new kinship study's lead author, Diego Alburez-Gutierrez, told CBC News.

This may be because much of that research is conducted in and on Western populations, where there's an assumption that extended kin "don't matter as much," said Alburez-Gutierrez, who leads the Research Group on Kinship Inequalities at the Max Planck Institute for Demographic Research in Rostock, Germany.

But research has shown that extended family plays an important role in individuals' lives in many cultures around the world, he added in an email interview.

"Disregarding cousins means that we ignore a 'weak' but important tie that individuals rely on for support and company at different stages of their lives."

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Statistics Canada doesn't specifically collect data on cousins, a spokesperson confirmed with CBC News.

But we do know the fertility rate is decreasing — currently the lowest on record, with a rate of 1.33 children per woman, according to Statistics Canada — and more people are choosing to have only one child.

According to the 2021 census, one-child families are the most common type in Canada, comprising 45 per cent of families with children that year (two child-families made up 38 per cent and three or more made up 16 per cent). The totals include one-parent families, common-law families and step-families.

This is a key factor in the cousin decline, said Prof. Yue Qian, an associate professor of sociology at the University of British Columbia whose research focuses on social demography.

"If this trend continues and more parents have only one child and stop at one child, their only child's kid [or kids] won't have cousins in the future," Qian said.

Further, more people aren't having children at all.

According to Statistics Canada, the proportion of women aged 50 and over who have no biological children is on the rise, at 17.4 per cent in 2022 compared to 14.1 per cent in 2001. In 2022, more than one-third of all people aged 15 to 49 said they intended to have no children.

"With fewer children and fewer siblings, there's just quite naturally fewer cousins in the mix," said Margo Hilbrecht, executive director of the Vanier Institute of the Family, a national, independent research institute dedicated to understanding families and family life in Canada.

Why cousins matter

Cousins take up an interesting space in many family dynamics — not quite siblings, not quite friends. Some people may grow up alongside their cousins and have a deep bond and others may rarely see them or speak to them at all. Yet experts agree the role can be an important one.

"It's one of the first places that we might encounter people of our own generation who hold different values or have a different way of doing things, and you wouldn't necessarily choose to be friends with all of them," Hilbrecht said.

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Extended family ties can be especially important for disadvantaged minority families, noted Qian. For example, she said, research shows that Black single mothers often rely on their extended kin for various types of support; gender and sexual minority adults face much higher levels of parental rejection.

"Extended kin, like cousins, could be a valuable source of social support" for people in these circumstances, she said.

Similar-age cousins, especially, can often enrich one's childhood in addition to having some shared experiences, said Tfaily. She said it's important to note the cousin decline is happening alongside other family-related changes, such as the decline in the number of aunts and uncles and the decline in the number of siblings.

"This is reshaping the experience of childhood compared to previous generations and affecting family dynamics and ties."

It's something that weighs on Lancastle when she compares how she grew up surrounded by extended family compared with the experience of her own children. Lancastle's father was one of 10 children; her mother was one of two.

"They're missing out on that big family experience, but I think I compensate by having good friends with kids the same age," she said of Nicholas and Charlie.

"But I knowingly did that because I want them to be surrounded by people."

This building of extended family by choice shouldn't be diminished, said Qian of UBC, noting that "voluntary kin" is common in many 2SLGBTQ+ communities, and we don't have to define family based on blood ties.

"If our society and culture celebrate and value developing close friendships and communities and building family we choose to a greater extent, we may not need to worry about a cousin decline so much."