This study examined the accuracy with which parents can judge their children's cognitive abilities, as well as the relation between parental accuracy and the level of the child's performance. Subjects were 50 second- and fifth-grade children, their mothers, and fathers. Each child responded to five cognitive tasks, and each parent predicted both how his or her child would perform and how children in general would perform on each task. Parents proved moderately but far from perfectly accurate, the dominant error being to overestimate their own child's ability. Accuracy did not vary as a function of the age or sex of the child or the sex of the parent; it did vary across tasks, however, and was greater for children in general than for the parent's own child. As in past research, accuracy was positively related to the child's performance: More accurate parents tended to have more competent children. The Discussion considers various explanations for this finding.
Miller, S. A., Manhal, M., & Mee, L. L. (1991). Parental Beliefs, Parental Accuracy, and Children’s Cognitive Performance: A Search for Causal Relations. Developmental Psychology, 27(2), 267–276. https://doi.org/10.1037/0012-16126.96.36.1997