Happy Fathers Day to:
Alan Scott, his kids don't know what to get him. Maybe a pride flag because they don't know their father enough. I doubt it though, just spending time with him would be good enough for him.
Jay Garrick who doesn't have actual children but is nearly everyone's grandfather, especially for the flash fam so he's probably getting cards or a new sweater to add to the collection.
Ted Grant, who forgot he had a son to begin with so I doubt he's receiving anything from Tom. Maybe a group gift from the Gym like new gloves. Or a cheesy fathers day card from Dinah.
Rex Tyler, who is dead so Rick isn't particularly doing anything other than mopping around or spending time with Jesse.
Johnny Chambers, Jesse is doing the same with Rick
Carter Hall, ?????? Poor Hector. His dad neglected him. He is absolutely not getting anything. Not like he'd remember what day it is anyway.
Ted Knight, uhhhhhhhh he's also dead(?) and so is David. Jack likes his father but he's busy being his own so maybe he'd send his dad like a tie or a tool he needs for inventions.
Wesley Dodds, not... Really. I mean he was a father figure to Sand but boy was that relationship a bit more toxic than the Bat/Robin apprenticeship.
Lawrence Crock, he's ISA but he's one of the better kick ass dad's... Sometimes. He's still a supervillain and turned his daughter into a weapon but he deserves some love.
Henry King Sr., I really shouldn't be saying happy fathers day to you because of all the SHIT you put Jr. Through...
All the legacy characters would send letters of gifts to their predecessors honestly or you know... Visit Graves.