I don't think boys growing up realize how important being a father is. Whether they had a great father, or an absent father, or a terrible father, many times they do not make the connection to the power they have over the next generation as a men. A father, or a lack of a father, shapes a child's life forever. 
In fact, it's been said that we view God in terms of how our father behaved. This isn't fair to God but it is certainly true. 
So as the song goes: Fathers be good to your daughters. A whole generation and possibly multiple generations are depending on it.