Jealousy protest to a social rival compared to a nonsocial rival in Chilean infants 10-20 months' old.

Jealousy protests have been linked to the intrusion of social rivals challenging infants' exclusive access to maternal care and resources that typically accompany attachment. Previous studies revealed that the experimental presentation of social rivals evokes protest in as early as 6 months old infants. This study replicated research on jealousy protests in a novel language and sociocultural context with 10-20 months old infants.