Most boys growing up need to be taught their strength, as when they are horsing around with their younger siblings. They are bigger, stronger, and much more influential let us say, than they think they are. But this need for teaching this lesson doesn't disappear when boys get past the horsing around stage. In their families, men are much more important, crucial and influential than they believe themselves to be.
It is the easiest thing in the world for a man to grow up, get married, have kids, and still think of himself the way he did when he was a boy. He believes that he is just one more person living in this household -- one of the roommates. But our perceptions are not authoritative, especially our perceptions of ourselves.
The Bible tells us that fatherhood is the font of the triune Godhead, and that all fatherhood here on earth is a reflection of that deep and ultimate fatherhood (Eph. 3:14-15). This means that, for good or ill, what a father does is potent. Words of reassurance, offered or withheld, are monumental in a child's growth. Words of encouragement, or exhortation, or patient teaching, are the same.
When a child has grown up under the devastation of unmitting harshness (and sometimes not so unwitting), or the devastation of neglect, the one thing a father may not say is that it "was not that big a deal." Of course it was a big deal. Your child is (hopefully) going to be praying the Lord's Prayer for the rest of his life. What will naturally, readily, come to mind whenever he starts, whenever he says, "Our Father . . ." What does that mean to him, and who taught it to him?
Many years ago I was teaching a class of high school kids at Logos, and it was during the time when awesome was the descriptor of pretty much everything. And I was at war with it. I would tell the class that the Grand Canyon is awesome, crab nebulae are awesome, and God is awesome. Your quiz scores are not awesome." I remember telling one bright young student there that I knew I could not make them stop saying that. But I went on to say that I could behave in such a way that, throughout the rest of their lives, whenever they said it, they would flinch, expecting an admonition from me.
It is the same kind of thing with fathers. You (whether you recognize it or not) are behaving in a way that will shape your children's understanding of what it means to be a father, and that understanding will occupy a central place in their lives. Are you their protector, or the principle thing they need protection from? Are you the provider, or the main impediment to provision? Are you the driving engine of joy in your household? or the central reason for depression?