Billy Collins explains the origin of Father's Day:
Today is Father's Day, a holiday in this country that goes back to a Sunday morning in May of 1909, when a woman named Sonora Smart Dodd was sitting in church in Spokane, Washington, listening to a Mother's Day sermon. She thought of her father, who had raised her and her siblings after her mother died in childbirth, and she thought that fathers should get recognition too. So she asked the minister of the church if he would deliver a sermon honoring fathers on her father's birthday, which was coming up in June, and the minister did. And the tradition of Father's Day caught on, though rather slowly. Mother's Day became an official holiday in 1914; Father's Day, not until 1972. Mother's Day is still the busiest day of the year forists, restaurants and long-distance phone companies. Father's Day is the day on which the most collect phone calls are made.
from A Writer's Almanac, June 16, 2013