To be fair, one or two out of every couple who have kids seem to either disappear or become incredibly busy, leaving them in the care of a grandfather who generally gives them limitless funds and access to dark magical artifacts. Grandpa Moto for example seemed to have been a poor father, not even noticing when Yugi's mom vanished, but was a great grandpa. https://www.amazon.com/How-Anime-Character-Clayton-Overstreet/dp/1441451803