"The character that dies is portrayed by an actor who won an Emmy for playing that character," he previously told TV Line.
"People who reported on it then reported we were killing an 'iconic' character; I'd like to say it's a great character, but I never used the word 'iconic'.
"It's a terrific character and it [happens in] our premiere this coming year.'
At the panel, Jean told how the character will get a death fitting of its importance to the show.
"It turned out bigger than we thought it was going to be," he explained, but hinted there won't be a mass cull as he added: "It's not going to be this blood bath where they all get murdered."
The Simpsons will return for its latest season on September 28 in the US with a Family guy crossover episode.
Family Guy producers were also at the panel and revealed that they pretty much have a carte blanche for the episode, with The Simpsons team giving them only a few notes, so expect it to be in the tone of the slightly more caustic cartoon.
- Independent