There are conflicting findings regarding the development of essentialist beliefs about social categories. The present studies address these findings by differentiating between the developments of the relative versus absolute essentialist status of categories. Participants were Israeli Secular Jewish and Muslim Arab kindergarteners, second graders, and sixth graders. Study 1 asked children which among alternative properties of a parent was most likely to transfer to a child. Findings showed that while kindergarteners did not systematically discriminate among properties, second and sixth graders privileged ethnicity. Study 2 asked children whether membership in various social categories was biologically or environmentally determined. Findings showed that kindergarteners and second graders, but not sixth graders, believed ethnicity to be biologically inherited. These results are discussed vis-à-vis different theories about the origins of social essentialism.