Every day, I'll focus on a specific Muppet and their history. Photos credit to @MuppetWiki.

Today’s Muppet of the Day is Uncle Louie! Louie stars in a 1970 Sesame Street sketch, in which he is asked by young Charlie in finding his way home. Charlie, as it happens, is Louie’s nephew, but he does not recognize his uncle with his police uniform on.
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Today’s Muppet of the Day is Genral Babbitt! The only soldier in the king’s army, Babbitt appears in the 1965 Cinderella pilot. Only he knows of the prince and Cinderella’s love, and his well-intentioned attempt to preserve it lead to their inability to recognize each other.
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How is this different from Hey Cinderella?
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That was more or less reworked from this pilot, which never aired on TV. Some characters were added or reworked and others dropped, with Babbitt among those not present in Hey Cinderella
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Today’s Muppet of the Day is Greta! Greta appears in Episode 2848 of Sesame Street, in a scene showing Elmo’s experience with Wubbaball. She excludes him because his fur isn’t the same color as her and her friends, a belief that leads to her friends leaving to join Elmo instead.
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Today’s Muppet of the Day is the Farmer! The overarching antagonist of the Tale of the Bunny Picnic is a gruff, surly farmer. He aims to cook the bunnies into a stew, despite the fact that, as Bean Bunny saves the day by exploiting, he is allergic to rabbits.
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Today’s Muppet of the Day is Lalo! Lalo was first seen on Sesame Street in season 53, but made a more prominent appearance the following season, practicing singing “Head, Shoulders Knees and Toes” in Spanish with Nina and Rosita in Episode 5411.
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Today’s Muppet of the Day is Fannie the Firefighter! Fannie participates in a nighttime rendition of “The People In Your Neighborhood” in episode 2619 of Sesame Street. Her part has her note that hours of work putting out fires does not put her out too.
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Today’s Muppet of the Day is Cap-Ten Kirk! Cap-Ten Kirk is one of the special guests at Numeric-Con, seen in Sesame Street episode 4504. After Green LanTen, Elmo’s favorite hero, leaves mid-convention, Cap-Ten Kirk joins Elmo in counting to ten, helping accomplish his goal.
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Today’s Muppet of the Day is Dora! Dora, a delightful damsel, is the heroine of the tale of The Diamond D and the Dangerous Dragon. She is given the former by her dad, and meets the dragon (dubbed Donald) when he tries to steal it (failing in part because she thinks he’s a dog).
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Today’s Muppet of the Day is the Inchworm! Though worms have appeared in Muppet form as far back as Sam and Friends, this inchworm, solid green in contrast to the standard striped worm, appeared in the Danny Kaye episode of The Muppet Show, joining Kaye as he sang The Inch Worm.
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Today’s Muppet of the Day is the Little Clam! A flamenco-playing little clam substitutes for Mary’s little lamb after he falls ill in episode 3326 of Sesame Street. Unfortunately, the substitution nearly causes the lamb to quit, as he fears he has been replaced outright.
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Today Muppet of the Day is Max! Max and his friend Telly visit Hooper’s Store in episode 1448 of Sesame Street, hoping to buy a set of jacks. When they find there is only one set left, Mr. Hooper helps them solve their debate with a guessing game.
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Today’s Muppet of the Day is Prunella! Prunella visits Mopatop’s Shop in the episode “Live Art”, searching for a painting of flowers. Puppyduck uses a magic paintbrush to paint a batch of flowers for her, but it is Moosey’s more traditional painting that catches her eye.
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Today’s Muppets of the Day are the Tortoise and the Hare! These renditions of the stars of the old fable visit Elmo’s World in the episode “Fast and Slow”. Their recollections of the fable inspire Elmo to imagine his own version of it.
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Today’s Muppet of the Day is Hubert the Human Cannonball! Hubert comes to Sesame Street in episode 4257, hoping to demonstrate his stunt of landing in a bucket of gelatin. His stunt attracts the attention of Elmo, Telly, Chris, and Baby Bear, who help him when his cannon breaks.
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Today’s Muppet of the Day is Vazh! Vazh is one of the six main characters in The Land of Gortch, aired in early installments of NBC’s Saturday Night (the future SNL). A serving girl, she doubles as King Ploobis’s affair partner, to Queen Peuta’s dismay.
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Today’s Muppet of the Day is P. Fenton Cosgrove! After Waldorf debuted, but before his character was fully established, the puppet was used in a pair of early Muppet Meeting Films. P. Fenton Cosgrove, as he was dubbed there, had a bad habit of drowsing off during meetings.
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Today’s Muppet of the Day is Old Mother Hubbard! Old Mother Hubbard, who checked the cupboard, is featured in the Mother Goose Stories adaptation of the nursery rhyme. Here, she is shown to have a poor memory, and the cupboard is bare is because she had forgotten to get a bone.
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Today’s Muppet of the Day is Larry Nooly! Larry is the protagonist of the Wubbulous World of Dr. Seuss episode “The Guest”. Initially unenthusiastic about staying at Lake Mulloon with his family, the Cat in the Hat lifts his spirits by showing him all there is to do there.
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Today’s Muppet of the Day is the Jabberwock! A Muppet Jabberwock appears in the Brooke Shields episode of The Muppet Show, during a segment retelling the Jabberwocky poem. Scooter, playing the hero, cuts its head off, but it survives (and is more inconvenienced than anything).
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