Young children enforce self-created norms promiscuously

Three-year-old children normatively protest the transgression of adult rules in a variety of contexts. Five-year-olds also normatively protest the transgression of rules they have themselves created collaboratively with peers. But do children of these ages protest rules that they have created for themselves as individuals? We prompted five-year-olds (Study 1: 128 participants, 69 females) and three-year-olds (Study 2: 64 participants, 32 females) to devise a way to play with a toy in the presence of some puppet peers, after which a new puppet engaged with the toy the 'wrong' way. Results showed that five-year-olds protested at similar rates regardless of whether they came up with a way to play collaboratively with others and then played together (collaborative condition), came up with a way to play individually but then played together (two trendsetter conditions), or came up with a way to play and played totally individually (solo condition). In Study 2, three-year-olds protested self-created rules as well, albeit at lower rates than five-year-olds. Finally, neither age group's protest seemed to be influenced by instructions containing explicit cues of normativity or conventionality (e.g., creating a game with rules vs coming up with a way to play). As such, when children create norms themselves, their willingness to protest novice transgressors seems not to be impacted by the degree to which these norms were created through collaboration. Moreover, our results show that promiscuous normativity of self-created norms emerges earlier than previously thought, around the same time children become promiscuous normativists towards adult-created norms.