For three decades, researchers have assessed children's genetic essentialism through an "Adoption Task," probing their beliefs about whether adopted babies grow up to resemble their birthparents or adoptive parents. The present study investigates these beliefs among children who were themselves adopted or donor-conceived (i.e., who share genetic material with neither or one parent, respectively; "ADC"), comparing them with children who were traditionally-conceived (i.e., who share genetic material with two parents; "TC"). Children (n = 95, 4-8 years old, 30ADC/65TC, 34M/59F/2NB, 55 White / 35 of color / five did not report) completed five trials of an Adoption Task concerning five personal characteristics (hair color, spoken language, personality, interests, and intelligence). Across trials, ADC children made fewer essentialist judgments than TC children (ηp² = .07); the odds of an essentialist response were threefold greater among TC than ADC participants. Exploratory analyses revealed that with age, children's essentialist judgments became increasingly differentiated across different characteristics (e.g., increasingly divergent views of the genetic basis of hair color vs. spoken language), and that this differentiation was more pronounced in the ADC than the TC sample. No differences were observed in the genetic-essentialist views of ADC and TC children's parents, suggesting that the mechanism underlying effects was children's own sense-making capacities. Whereas nature and nurture are confounded for TC children, these factors are decoupled for ADC children, supporting them in building their causal theories. Cognitive, developmental, and social implications are discussed, along with translational implications for ADC children and their families. (PsycInfo Database Record (c) 2024 APA, all rights reserved).