Both couples forsake the honorable choice in order to follow their hearts, sparking unanticipated consequences. They each wed in secret, outdoors under a tree, while officiated by a maester. Each couple conceives a baby shortly after the vows are exchanged, and each couple eventually dies as a result of their emotional decision-making and broken commitments.
Both marriages had tragic, fatal outcomes, proving that — at least in the scheme of Game of Thrones — emotional decisions can be foolish. Perhaps that is why Tyrion Lannister looks so disappointed as Jon Snow and Daenerys Targaryen begin their own romantic tryst; he knows that they're each prone to rash action based on their strong feelings, and when love is involved, it's bound to have consequences.
Here's to hoping that Jon and Dany take notes from their families' respective marriages to avoid the same sort of runaway consequences in season eight. We're not sure we could handle another heartbreak like the Red Wedding.
