Even his friend said he's bad: Children think personal alliances bias gossip.

Children learn about other people through gossip. Although gossip can be a valuable and efficient way to learn about others, evaluating gossip's credibility requires understanding when people may be biased, and using this information to update the truth-value placed on the gossip. For instance, people may be motivated to improve their and their friends' reputations (or to worsen their enemies' reputations). Therefore, testimony that cuts against these social motivations may be more credible. Here, in four studies with 3- to 13-year-old children (total N = 860), we examined (1) children's expectations about the type of gossip people were likely to spread about friends versus enemies, and (2) children's ability to discount testimony that is in line with a speaker's social biases (e.g., negative testimony about a friend). We found that children expect speakers to say nice things about their friends, and mean things about their enemies. And, children were less likely to endorse potentially biased testimony, though the strength of their ability to avoid endorsing biased testimony varied based on the domain of testimony. Overall, these studies suggest that children expect a speaker's testimony to be systematically biased based on her relationships. Our results underscore the importance of tracking and using relationships when evaluating testimony, because relationships have immense power for helping us effectively make sense of an ambiguous world.