Society finches must be in a nesting cycle themselves before they take on parenting duties. There are exceptions, and some individuals, pairs or even trios begin to set and incubate properly upon offering them a clutch of eggs. Societies can be coaxed into nesting behavior by offering them a clutch of artificial canary eggs. If they begin to sit tightly, it’s usually safe to switch them out for real eggs. The best odds of success in fostering come from beginning with eggs rather than already hatched chicks.