With 21-Across, “The Simpsons” character who is a children’s TV host Crossword Clue

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The answer to the crossword clue "With 21-Across, “The Simpsons” character who is a children’s TV host" is Krusty the Clown. 

The answer to 21-Across is "THE CLOWN", so when you combine the two clues, it's referring to Krusty the Clown, who is a children's TV host in the animated sitcom "The Simpsons". He is known for his raspy voice, his trademark orange hair, and his oversized shoes. Krusty is often portrayed as being greedy and self-centered, but he also has a good heart and cares about his fans.

Krusty is voiced by Dan Castellaneta, who also voices Homer Simpson and many other characters on the show. He was created by Matt Groening and was first introduced in the show's second episode, "Bart the Genius". Krusty has become one of the most popular characters on "The Simpsons" and has appeared in numerous episodes and specials.