This prospective, longitudinal investigation examined differential consistency of three core dimensions of individuality from toddlerhood through middle childhood. Data came from 273 families who participated with their child at least once during three developmental periods: toddlerhood (2 years), early childhood (3 to 5 years), and middle childhood (6 to 10 years). Both mothers and fathers reported on attributes of their child using subscales from the Toddler Behavior Assessment Questionnaire, the Child Behavior Questionnaire, and the Iowa Personality Questionnaire. Reports were used as indicators of the latent "Big Three" dimensions of positive emotionality, negative emotionality, and constraint at each of the three developmental periods. Results pointed to consistency in these broad dimensions of temperament and personality from toddlerhood to middle childhood.