The happiest parents are—drumroll, please—parents with four or more kids.

Parents of large families were found to have the most life satisfaction, according to a study by Australia’s Edith Cowan University. Dr. Bronwyn Harman, of the psychology and social science school at the university, spent five years studying what types of families are most content.

“[The parents] usually say they always wanted a large family, it was planned that way, and it was a lifestyle they’d chosen,” Harman told The Sydney Morning Herald.

During her five-year study, Harman interviewed hundreds of parents from different family makeups. Her findings are based on resilience, social support, self-esteem, and life satisfaction.

Her research points out that parental happiness relates to how much effort has been put into growing the family.

“What is important for kids are things like consistency, boundaries and [to] know that they are loved, no matter what,” Harman tells ABC Australia.

Prior to the study, Harman thought parents with more children would be less happy.

Though larger families may have more chaos and expenses than a smaller family, Harman’s research shows that these issues are balanced by the amount of joy received from having more children.

Her findings show that children who grow up in large families learn independence at a young age and always have someone to play with.