We explored the role of parental testimony in children's developing beliefs about the ontological status of typically unobservable phenomena. US parents and their 5-to 7-year-old children (N = 25 dyads) separately rated their confidence in the existence of scientific and religious unobservable entities (e.g., germs, angels), and were invited to engage in an unmoderated dyadic conversation about the entities. Both parents and children were more confident in the existence of the scientific entities compared to the religious entities. Parental religiosity predicted the strength of their belief in the religious entities, and these beliefs were positively associated with their children's judgments in the religious domain of religion. We coded parental testimony produced during the unmoderated conversation for a number of subtle linguistic cues that convey their confidence and prevailing beliefs in an entity's existence. The results revealed consistent cross-domain differences: parents expressed more uncertainty, were more likely to mention variation in people's beliefs and make explicit claims about the ontological status of the religious, as compared to the scientific entities. However, with increasing religiosity, parents produced fewer cues to uncertainty, mentioned belief variation less often, and were more likely to make claims of endorsement when talking about the religious unobservables. Importantly, the pattern of coded linguistic cues in parental testimony was significantly associated with children's ontological judgments. The present findings have implications for understanding the socio-cultural mechanisms by which confidence in the existence of invisible agents and processes develops in childhood. Although we are not able to directly experience or encounter many everyday causal phenomena, beliefs in the existence of these phenomena can have a powerful influence on our behavior. For example, in the months succeeding the declaration of the global COVID-19 pandemic by the World Health Organization (WHO, 2020), psychologists have sought to understand the perceptions and motivations that lead to commitments to public health practices that can halt the spread of the invisible, yet highly infectious, virus (see Van Bavel, Baicker, & Boggio et al., 2020, for a review). Similarly, belief in the causal efficacy of both scientific and supernatural remedies, such as vaccines and prayer, influences the behaviors that adults and children engage in to protect themselves (Legare, Evans, Rosengren, & Harris, 2012; Rutjens & Preston, 2020). An open question is just how beliefs CONTACT Kathleen H.

We explored the role of parental testimony in children’s developing beliefs about the ontological status of typically unobservable phenomena. US parents and their 5- to 7-year-old children (N = 25 dyads) separately rated their confidence in the existence of scientific and religious unobservable entities (e.g., germs, angels), and were invited to engage in an unmoderated dyadic conversation about the entities. Both parents and children were more confident in the existence of the scientific entities compared to the religious entities. Parental religiosity predicted the strength of their belief in the religious entities, and these beliefs were positively associated with their children’s judgements in the domain of religion. We coded parental testimony produced during the unmoderated conversation for a number of subtle linguistic cues that convey their confidence and prevailing beliefs in an entity’s existence. The results revealed consistent cross-domain differences: parents expressed more uncertainty, were more likely to mention variation in people’s beliefs and make explicit claims about the ontological status of the religious, as compared to the scientific entities. However, with increasing religiosity, parents produced fewer cues to uncertainty, mentioned belief variation less often, and were more likely to make claims of endorsement when talking about the religious unobservables. Importantly, the pattern of linguistic cues in parental testimony was significantly associated with children’s ontological judgements. The present findings have implications for understanding the socio-cultural mechanisms by which confidence in the existence of invisible agents and processes develops in childhood.