A father is often the parent whose love was hardest to read in real time and easiest to read in retrospect. The years he showed up for the school plays. The years he sat in the truck in the driveway. The year you finally understood what he was carrying. A song for him is the chance to read it back to him on the record.
What this kind of song holds
Memorial songs for fathers hold the labor and the silence. They hold what he taught and what he learned too late. They hold the moments when he was a boy and the moments when he became the man you knew. The best ones don't try to translate him; they let his particular weather come through.
What to put in the intake
Give us his trade, the place he came from, the song he sang badly in the car. Give us the moment he hugged you when you didn't expect it. Give us what he said when he said anything important. We use those specifics as load-bearing beams, not decoration.