Jennifer Aniston was the voice behind Mrs. Stevens in South Park

Jennifer Aniston was the voice behind Mrs. Stevens in South Park Season 3, titled "Rainforest Schmainforest".

Mrs. Stevens is the faculty chaperone for the choir. In this animation, Mrs. Stevens recruits the South Park kids to have a visit to the rainforest to perform their activist song. 

Unfortunately, they got lost in the rainforest and Mrs.Stevens attacked by giant bugs and was captured for a tribal sacrifice. 

That time Aniston and Pitt were a couple.

Parker recalled, "This show too was cool because Jennifer Aniston came in and did a voice. Apparently her and Brad were fans and so she wanted to come in and do something."

Then he added, "She was really, really nervous. I remember when she came in to do the voice, we had the script for her. She got in the booth, in front of the mic with headphones on and she was visibly shaking. She was really nervous."