Five-year-old children tend to be generous to their peers only when they are being observed — just like adults or older children, a new Yale University study shows. A study appearing online Oct. 31 in the journal PLOS ONE, showed that five-year-old participants handed out fewer stickers to peers when the recipients did not know how many they had. Children also handed out fewer stickers when recipients could not see them. Children only became more generous when the recipients could both see them and knew how many stickers they had to give. “At a surprisingly early age, children are already employing their generosity in strategic ways,” said Kristin Leimgruber, lead author of the study and graduate student in the lab of senior author Kristina Olson, professor of psychology.