Board Thread:Character Discussion/@comment-25325271-20141006003753/@comment-5106672-20141016021033

Well, my father's oldest sister is a few months younger than my maternal grandmother, and his youngest brother is my mom's age. The aforementioned aunt has a daughter (my cousin) who is just a couple of years younger than my mother, and I myself am just a few years older than my eldest cousin once removed. So I missed such a situation in my family just narrowly and can confirm it is indeed very possible. Perhaps not common, but quite normal.

So yeah, I've got an aunt and uncle with a 25 year age gap without the Dark Curse; in the Onceverse it can very well be more plausible!