Merrett Frey, mocked as Merrett Muttonhead, was the ninth son of Lord Walder Frey and the fourth born of Walder's marriage to Amarei Crakehall, and the point-of-view character of the epilogue of A Storm of Swords. Robust in his youth, he served Lord Sumner Crakehall as page and squire alongside Jaime Lannister, but a mace-blow that shattered his helm in the campaign against the Kingswood Brotherhood left him with crippling headaches that ended his hope of knighthood; an earlier capture by Wenda the White Fawn, who branded a fawn upon his backside, made him a byword for misfortune. Returned to the Twins in disgrace, despised by his father and his wife Mariya Darry, he became the greatest drunk in the castle, fathering several daughters — among them Walda, who wed Roose Bolton.
At the Red Wedding, Merrett was charged by Lame Lothar with drinking Lord Jon Umber insensible, a task he failed when the Greatjon proved too tough to subdue. When the Brotherhood Without Banners seized his kin Petyr Pimple, Merrett carried a hundred golden dragons to Oldstones to ransom him, only to find the boy already hanged in the godswood. Though he protested that he had done nothing but drink and named the true plotters, the risen Catelyn Stark — now Lady Stoneheart — judged him guilty all the same, and he was hanged by the outlaws near Oldstones in 300 AC, aged seven-and-thirty.