Midway through House of the Dragon episode 6 “The Princess and the Queen,” King Viserys I (Paddy Considine) gathers his Small Council together to talk about the important political issues of the day. On the docket, as it always seems to be, is a bit of drama in the Riverlands. House Bracken and House Blackwood are at each other’s throats again and the dominant house in the region, House Tully, has requested the Iron Throne’s help in settling the matter. This scene serves as an important development in Princess Rhaenyra Targaryen (Emma D’Arcy) and Queen Alicent Hightower’s (Olivia Cooke) evolving hostilities. For the first time viewers get to see how both rivals have differing opinions on how to best govern the realm. Beyond just that, however, the scene also serves as confirmation that one of “A Song of Ice and Fire” author George R.R. Martin’s goofiest jokes has made its way into the House of the Dragon unscathed. What is that joke, you ask? Well it might be helpful to recall what the name of the current Lord Tully of Riverrun is: Lord Grover Tully. Still not connecting? What if I told you that Lord Grover’s future grandson will be named Elmo? And Elmo’s sons will be named Kermit and Oscar? That’s right: Sesame Street has come to Westeros! Grover, Elmo, Kermit, and Oscar all made their debut in Fire & Blood, the fictional “history” book upon which House of the Dragon is based. Archmaester Gyldayn describes the disposition of Grover’s descendants thusly: “Then as now, the riverlords were a fractious, quarrelsome lot. Kermit Tully, Lord of Riverrun, was their liege lord, and nominally commander of their host…but it must be remembered that his lordship was but nineteen years of age, and “green as summer grass,” as the northmen might say. His brother Oscar, who had slain three men during the Muddy Mess and been knighted on the battlefield afterward, was still greener, and cursed with the sort of prickly pride so common in second sons.” Kermit is “green as summer grass?” eh? And Oscar is cursed with a sort of “prickly pride” huh? After the book’s publishing, Martin’s World of Ice and Fire co-authors (and webmasters of Westeros.org) Elio M. García and Lina Antonsson confirmed that the muppet connections were all very deliberate. The colors mentioned in that tweet refer to the three colors of the various “forks” of the mighty central Westeros river The Trident. It just so happens that they all correspond to three of the muppets chosen as Tullys: Elmo (red), Kermit (green), and Grover (blue). It’s also worth noting that House Tully isn’t some obscure entity in Westeros. They’re a very big deal as evidenced by Catelyn Stark, Lysa Arryn, Edmure Tully, and Brynden “Blackfish” Tully’s presence on Game of Thrones. Next time you rewatch the series, bear in mind that Catelyn Stark has some muppet DNA in her ancestry. Befitting the status of their influential house, all four Sesame Street Tullys (Grover and Kermit in particular) actually end up playing a sizable role in the Dance of the Dragons – the Targaryen civil war that will be depicted in House of the Dragon. As evidenced by his brief mention in episode 6, Grover Tully has a modest role to play near the beginning of the war. Then Elmo Tully will play a similarly sized role before Kermit Tully comes in at the very end to become a major player in the Seven Kingdoms’ reconstruction era. New episodes of House of the Dragon premiere Sundays at 9 p.m. ET on HBO and HBO Max in the U.S. and Sky Atlantic in the U.K.