My father didn't happen to be lifelong friends with the Sheriff, that's all.

This was not because the father happened to be of high status and held various important positions within the government.

Henry was 9 before his father happened upon one of his games.

My father happened to be writing a book; dimly I realized this answer would not serve.

By chance, father and son happened upon each other in a crowded street.

When the picture appears in the paper, Violet's father happens to see it and gets angry at her.

Well, for your information I'll tell you that the father of my child doesn't happen to be Mike.

She would keep him down there for hours at a time, sometimes a whole day, if his father happened to be away from home.

Even if his father happens to be holding office some place else?

My father just happened to believe that a girl is every bit the equal of a boy and should learn to use a gun too.