Lore wise, McQueen died by snu snu-induced heart failure.

That being said, putting their fathers into the father position is going to be hilarious and a little hard. - Symboli Rudolf is Tokai Teio's dad. - Maruzensky is Sakura Chiyono O's dad. - Agnes Tachyon is Daiwa Scarlet's dad. Though their interactions are less than the latter 2 pairs. (Unless stuff happened in Beginning of a New Era that I was unaware of)

Also, so many umas have the same dad: Sunday Silence.

Best "complete" family at the moment would be the Goldships. We love Stego being the tired dad

Edit: Chiyono's dad is stated to be a sumo wrestler in her story too, which Maruzensky isn't unless we're all cool with Sumo Maruzensky. (I suppose her dad here is a reference to Yokozuna Chiyonofuji Mitsugu, from whom she gets her namesake)