I was watching a discussion between Elio and Linda, co-authors of The World of Ice and Fire and founders of Westeros.org, on Annullments in Westeros, in light of recent developments in the show.
Linda says in that video:
We do have an example of course from The World of Ice and Fire where children who were produced prior to marriage were rendered legitimate by the marriage.
I realized that I didn't know which example is she talking about?
Which bastards were rendered legitimate upon their parents marriage in Westerosi History?