Kit Harington's brother snuck *that* 'Game of Thrones' line into his wedding speech

You know the line. It follows Game of Thrones star Kit Harington around everywhere he goes, including to his own wedding.

Your ol' pal Jon Snow caught up with Jimmy Fallon on The Tonight Show on Thursday, ahead of the premiere of Season 8 on Apr. 14.

Of course, the iconic line, "You know nothing, Jon Snow," came up, which Harington said is regularly shouted at him and his wife Rose Leslie, who said the line as Ygritte in the show.

But even Harington's brother dropped it at a highly inopportune time.

"I hate it when people say it, and my brother managed to get it into the end of my best man speech," he said. 

"It was quite sweet actually, he said, 'But looking at the woman you're marrying, it shows you do know something, Jon Snow."

Aw. Free pass.