King Rupert the Second is a modified version of King Goshposh, as seen in the 1971 TV special The Frog Prince. A full-bodied variation of the earlier fairytale monarch, King Rupert has a fringe of white-hair and lacks Goshposh's ubiquitous cigar. Otherwise, the voice and personality are essentially identical.
The king is the father of Princess Melora, and the son of King Rupert the First. As the story opens, the gullible Rupert believes Taminella Grinderfall's lies, including her claim to be his sister. He also doesn't know the difference between frogs and toads.
The story's plot hinges on Melora, Robin and Kermit's attempts to convince King Rupert that "Aunt Taminella" is a wicked witch. Unfortunately, the king doesn't listen to amphibians, and he's too foolish to understand Melora's "wackbirds" speech. At the end of the story, the king retires, after many happy years "as a scheming despot."