This study presents data on the initiation of positive affect during m
other-child interaction in 12- (n = 31), 18- (n = 28), 24- (n = 30), a
nd 32- (n = 25) month-olds. The proportion of child-initiated and prom
pted episodes increased with age, whereas that of mother-initiated epi
sodes decreased, indicating that children are increasingly active part
ners.