When you think about, it all holidays are basically the same -- days of celebration, all similar, just with different names.
Father's Day, Mother's Day, Thanksgiving, Valentine's Day, Memorial Day, BIrthdays and the million other "days" that we celebrate are all pretty much one and the same thing: days where we stop to celebrate life, sometimes past, but usually present.
It's about the love...for life: a time to sing out on the positives and to vow to live each day to the fullest.
Hence I think it appropriate on this "day" (or any) to re-watch that celebratory scene from Hal Ashby's 1971 film Harold and Maude (avail on DVD @ Amoeba) in which Ruth Gordon and Bud Cort's characters sing Cat Stevens' "If You Want To Sing Out, Sing Out." Immediately below that clip is Cat Stevens performing "Father and Son." Another appropriate Father's Day song is the 1991 hip-hop single from Ed O.G. & da Bulldogs "Be A Father To Your Child." The third video below is "Father and Daughter" which is "animacion con acuarela por Michael Dudok de Wit," and below that is "Father's Day Poem: to Dad" -- a stop motion animation by YouTuber indiestopmotion.