If HBO ever makes Game of Thrones season 9, then it would be able to add more weight to Jon Snow killing Daenerys Targaryen, without her return.
In Game of Thrones season 1, episode 2 "The Kingsroad," the dagger is wielded by a Northman - a catspaw sent to assassinate Bran Stark. Bran's mother, Lady Catelyn, who is present in Bran's room ...