Previous work has shown the robust nature of gender bias in both children and adults. However, much less attention has been paid toward understanding what factors shape these biases. The current preregistered study used parent surveys and child interviews to test whether parents' conversations with their children about and modeling of gender intergroup relations and/or children's self-guided interests about gender ("self-socialization") contribute to the formation of gender attitudes, status perceptions, and gender intergroup behaviors among young 4- to 6-year-old children. Our participant sample also allowed us to explore variation by child gender, ethnicity (Asian-, Black-, Latiné-, and White-American), and U.S. geographical region (Northeast, Pacific Northwest, West, Southeast, and Hawaii). Data suggest that children whose parents reported they were especially active in seeking information about gender tended to allocate more resources to same-gender versus other-gender children and expressed less positive evaluations of other-gender children in comparison to children who were less active. By contrast, we found that parents' conversations with their children about gender intergroup relations and about gender-play stereotypes showed few connections with children's gender attitudes. In terms of demographic differences, boys raised in households with more unequal versus equal division of labor perceived that men had higher status than women, but few differences by ethnicity or geographic region emerged. In sum, our study suggests that both self- and parent socialization processes are at play in shaping early gender attitudes, status perceptions, and gender intergroup behavior, although self-socialization seemed to play a larger role.