Sunday's episode of "The Simpsons" paid tribute to the late Marcia Wallace in the series' opening sequence.
Every episode usually opens with Bart writing a different message on a classroom chalkboard starting "I will not …" over and over again as a form of punishment.
During Sunday's episode, one single sentence was seen on the familiar board: "We'll really miss you Mrs. K."
Late last week, Wallace passed away from breast cancer. She voiced fourth-grade teacher Mrs. Edna Krabappel for 23 years.
Series executive producer Al Jean said in a statement the show will retire the character as a result of Wallace's passing.
SEE ALSO: 'The Simpsons' will retire Mrs. Krabappel after Marcia Wallace's death