[Buckeye McFrog]

Lifelong friend of Lucille Ball until she guest starred in an early 60’s episode of The Lucy Show. Lucy was unhappy with some aspect of her performance and dressed her down in front of the studio audience. Supposedly they never spoke again.

[oh8eleven]

"Lucille Ball was notoriously abusive to her co-stars. Joan Blondell made an appearance on the show, and Ball told her she "stunk" in-between takes. Blondell responded in front of the audience: "F--k you Lucille Ball!""

Source = https://www.imdb.com/title/tt0055686/trivia