The family returned to Toronto for a time in 1934-35, heading back to England again in 1936 before returning to Toronto for good in 1939. She purchased a home at 3590 Bayview Avenue the same year, eventually adding two wings to what would become a 17-room mansion. Originally built in 1922, de la Roche lived in the home until 1945 when she and her family relocated to Forest Hill where it was easier to secure staff and get the children to and from school. During this era, de la Roche reliably published at least one book a year, sometimes more. However, although her early work had received positive critical notices, critical reaction to her newer works was often decidedly cool, in both North America and Europe. Nevertheless, the "Jalna" books were still strong sellers, with a wide and appreciative readership.