Your child's primary relationship with his/her father can affect all of your child's relationships from birth to death, including those with friends, lovers, and spouses.
Girls will look for men who hold the patterns of good old dad, for after all, they know how "to do that." Therefore, if father was kind, loving, and gentle, they will reach for those characteristics in men. Girls will look for, in others, what they have experienced and become familiar with in childhood. Because they've gotten used to those familial and historic behavioral patterns, they think that they can handle them in relationships.
Boys on the other hand, will model themselves after their fathers. They will look for their father's approval in everything they do, and copy those behaviors that they recognize as both successful and familiar. Thus, if dad was abusive, controlling, and dominating, those will be the patterns that their sons will imitate and emulate. However, if father is loving, kind, supportive, and protective, boys will want to be that.
It is impossible to over-estimate the importance of dad. For example, girls who have good relationships with their fathers tend to do better in math, and boys who have actively involved fathers tend to have better grades and perform better on achievement tests. And well-bonded boys develop securely with a stable and sustained sense of self. Who we are and who we are to be, we are becoming, and fathers are central to that outcome.