Board Thread:General Discussion/@comment-33430271-20171029000130/@comment-40070179-20200121233044

After a ton of research, I'm confident that Rune's parents must have both donned the Curse of the Gray Fox.

First, the curse wasn't on just one Gray Fox, but whoever had worn the Gray Cowl of Nocturne. This means that the curse would spread to another person should they acquire the Cowl and still affect all individuals who had worn the Cowl.

Second, when Corvus (the Gray Fox at the time) is freed from the curse, he gives the Cowl to the Hero of Kvatch, unknowingly passing the curse to the Hero. This explains why the Hero's name, race and gender are not specifically detailed in Skyrim.

Third, given the specific phrasing in the letter to Rune "No Word Yet" details that his parents had "completely erased themselves from history." A feat only known to have been caused by the Curse on the Gray Cowl of Nocturne.

So while it's safe to assume that Rune's parents had acquired the Curse and left Rune behind for any number of reasons, the runes/markings on the lids of the Jars containing insects seem to have no discernable connection to Rune's parents.