Given the anime has gone nearly twenty five years with only one line in the second episode attributed to mentioning or characterising Ash’s father, I’m perfectly fine if he’s never mentioned or alluded to again. Maybe there’s some bigger scope reason for his absence like time travel, but Ash, Delia, Oak and Gary have never mentioned him or alluded to his absence in their lives. Maybe if Ash had acted like he was trying to impress an absent or emotionally absent father, but the closest we get to Ash’s paternity is in the Pokemon Live stage performance (which is of dubious canon anyway). I haven’t seen the Secrets of the Jungle movie as it’s not available where I am.
That raises the question of Gary’s parents. His sister isn’t even adapted into the anime. The games don’t do anything to explain it either, so most likely they died and the lack of a parental figure besides Oak could have contributed to the egocentric personality Gary has during the Indigo League. Delia as a maternal figure for Gary as he and Ash were growing up is another interesting potential backstory even though they don’t interact at all.
That raises the question of Gary’s parents. His sister isn’t even adapted into the anime. The games don’t do anything to explain it either, so most likely they died and the lack of a parental figure besides Oak could have contributed to the egocentric personality Gary has during the Indigo League. Delia as a maternal figure for Gary as he and Ash were growing up is another interesting potential backstory even though they don’t interact at all.