Transgender and cisgender children's essentialist beliefs about sex and gender identity.

Children essentialize gender from a young age, viewing it as inborn, biologically based, unchanging, and predictive of preferences and behaviors. Children's gender essentialism appears to be so pervasive that it is found within conservative and liberal communities, and among transgender and cisgender children. However, it remains unclear what aspect of gender the children participating in past studies essentialized. Such studies used labels such as "girl" or "boy" without clarifying how children (or researchers) interpreted them. Are they indicators of the target's biological categorization at birth (sex), the target's sense of their own gender (gender identity), or some third possible interpretation? This distinction becomes particularly relevant when transgender children are concerned, as their sex assigned at birth and gender identity are not aligned. In the present two studies, we discovered that 6- to 11-year-old transgender children, their cisgender siblings, and unrelated cisgender children, all essentialized both sex and gender identity. Moreover, transgender and cisgender children did not differ in their essentialism of sex (i.e., whether body parts would remain stable over time). Importantly, however, transgender children were less likely than unrelated cisgender children to essentialize when hearing an ambiguous gender/sex label ("girl" or "boy"). Finally, the two studies showed mixed findings on whether the participant groups differed in reasoning about the stability of a gender-nonconforming target's gender identity. These findings illustrate that a child's identity can relate to their conceptual development, as well as the importance of diversifying samples to enhance our understanding of social cognitive development.