Research on "parentese," the acoustically exaggerated, slower, and higher-pitched speech directed toward infants, has mostly focused on maternal contributions, although it has long been known that fathers also produce parentese. Given recent societal changes in family dynamics, it is necessary to revise these mother-centered models of language input. Using a longitudinal dataset of daylong recordings collected with the same group of USA-born English-speaking infants (N = 21) at 6, 10, 14, 18, and 24 months, we investigate the similarities and differences between maternal and paternal parentese quantity, as well syntactic and lexical characteristics of parentese. We find that mothers are producing "quantitatively" more parentese than fathers at all ages. We find that the syntactic aspects do not differ substantially between mothers and fathers, however lexical differences do emerge. Specifically, we see that mothers may use more question and mental state words than fathers. Furthermore, use of these types of words increase as the child develops. This research highlight the continued need to further study fathers in order to have a full understanding of child language development.