
Quick answer — Minoru Hirata worked on Grandpa and Grandma Turn Young Again (Animation Producer), Danchigai (Theme Song Lyrics), Ojisan and Marshmallow (Music) and 2 more anime.
Minoru Hirata worked on Grandpa and Grandma Turn Young Again (Animation Producer), Danchigai (Theme Song Lyrics), Ojisan and Marshmallow (Music), Danchigai Special (Theme Song Lyrics), Peter Grill and the Philosopher's Time (Insert Song Lyrics).