Children become better readers if their father reads to them, not just their mother, new research has found.
But the study, conducted by the Murdoch Children's Research Institute in Australia, doesn't say why this is the case.
"It's a good question, but unfortunately we can't answer that," Professor Sharon Goldfeld, group leader in policy, equity and translation, told Melbourne radio station 3AW.
"What we do know is that fathers reading makes a difference.
"Engaging around the story is really important, that kind of sing-song, talking back and forwards with the child."
Dads who read to their children as toddlers have four-year-olds with better language and literacy skills, according to the research, which looked at data from the Let's Read study of 405 families.
The effect could be seen regardless of either parent's education or the mother's reading practises.