The only thing Jennifer Lawson can't seem to write into her family's daily calendar is free time.

The blank space of each fresh day vanishes in scribbles of ink as she documents air-cadet meetings for her two eldest sons, both from a previous marriage; regular visits from one of her husband's three daughters; and endless sports activities for the couple's four natural children.

Co-ordinating the sleep, schooling and social needs of a sprawling blended family — nine kids in all, ranging in age from 20 months to 20 years — could be a full-time job all on its own. But for Lawson, 39, it's the least of the many issues confronting an increasingly common brand of Canadian family unit.

"When you're getting together with a blended family, you could still have court cases going on, you have work challenges, you have personal challenges," Lawson said on the phone from her home in Grimsby, Ont., an hour's drive down the road from Toronto.

"You don't realize that all those little things can make things like blended families even more difficult."

It's a complex — and often physically and emotionally bruising — reality with which a growing number of Canadians are having to come to terms, suggest fresh census numbers released Wednesday by Statistics Canada.

First count

Stepfamilies, counted in the census for the first time in 2011, comprised 12.6 per cent of Canada's 3.7 million families with children, the agency reported. Those families are home to nearly 558,000 children aged 14 and under, about 10 per cent of all those living in a private household.

Statistics Canada defines a stepfamily as one in which at least one child was the biological offspring or adopted child of only one of the spouses prior to the relationship. From there, stepfamilies are classified either as "simple" or "complex," depending on the children and their biological or legal relationship to the parents.

A "simple" stepfamily comprises biological or adopted children from one and only one of the spouses, all of them pre-dating the relationship.

There are three types of "complex" stepfamilies: those with at least one child of each parent and no children of both; at least one child of both parents and at least one from only one parent; and children from both parents and at least one from each.

Last year marked the first time Canadian stepfamilies been formally counted in the census, although Statistics Canada has been keeping tabs on the trend since at least the mid-1990s.

In 2001, the agency warned that a growing divorce rate, coupled with the mounting popularity of common-law relationships would make it more likely that a growing number of Canadian children would grow up in a reconstituted family.

In its general social survey in 2006, the agency found that only about 40 per cent of those families surveyed could be considered "intact" — two people and their own biological or adopted offspring.

The numbers reflect one of the most significant shifts in Canada's population in the past 40 years, said Roderic Beaujot, a family demographer at Western University in London, Ont.

Decades of evolving families

The stereotypical Brady Bunch family unit began evolving as early as the 1970s, Beaujot said. New laws, such as the Divorce Act in 1968, loosened societal restrictions on the family unit and how relationships and child-rearing ought to evolve.

"We have more diversity of relationships, including an orientation that it's good to have diverse potential relationships over the life course," Beaujot said. "People can make their own choices in this regard."

Lawson didn't realize just what repercussions those choices could have when she decided to marry her husband and merge their existing families a decade ago.

Eight of those years were then spent mired in court battles as the couple hammered out complex visitation arrangements for both sets of children.

Those legal proceedings took a financial toll on a family that continued to grow as Lawson and her husband welcomed new kids of their own.

More daunting, however, were the challenges of helping children of widely varying ages adjust to a new and complex family dynamic.

The Lawsons found themselves alternately offering guidance and letting their children take the lead as they established new routines in every facet of everyday life.

The kids grappled with a bewildering number of issues, including what to call their new step-parents, how to obtain multiple copies of official school documents, and how to manage time divided between at least two households, Lawson said.

The parents tasked with shepherding them through these pitfalls had to do so under tremendous emotional strain, Lawson said. She and her husband struggled to prioritize their children's feelings without entirely suppressing their own.

"For every ying, there's a yang," she said.

"You have to understand that your perspective of what happened is not necessarily the other person's perspective. We try and take that into consideration. We really try and think about, in the end, it's not us, it's about the kids."