Associations between home literacy environment and children's reading ability are often assumed to reflect a direct influence. However, heritability could account for the association between parent and child literacy-related measures. We used data from 101 mother/father/child triads to consider the extent to which associations between home literacy and children's reading fluency could be accounted for by parental reading fluency. Although home literacy correlated significantly with children's reading, no variable predicted significant variance after allowing for parental reading, except the number of books in the home. By incorporating measures of heritable parental traits into studies investigating home environment effects, we can start to identify which variables are correlates of parental traits and which might play a causal role in fostering children's development.