“Hurry give me mouth nipple.”

That’s one of the last things Koko the gorilla said during an interview with AOL in 1998. Even though she could communicate around 1,000 words in American Sign Language and reportedly understood around 2,000 English terms,“nipple” was a word the celebrity ape loved and used often. In that brief interview with AOL, she signed it nine times.

Koko the gorilla gained fame in the late 1970s when her handler, Francine “Penny” Patterson, taught her ASL beginning at the age of 1 in a bid to prove and further research on interspecies communication. Because of her unique abilities, Koko — who passed away in her sleep at the age of 46 on June 19, 2018 — became one of the most famous living gorillas, changing the way science perceives communication and emotion in great apes.

She appeared on the cover of National Geographic a few times, starting in 1978 when Patterson handed her a camera and instructed her to snap a photo of herself in a mirror, essentially taking a “selfie.” PBS, BBC, and indie filmmakers made documentaries about her and tabloid magazines regularly included photos of the popular primate within their pages. A multitude of children’s books and stuffed animals were inspired by Koko, as well as the Michael Crichton novel, and subsequent movie, Congo — about a female gorilla fluent in sign language who helps explorers locate a tribe of monkey-human hybrids in the African rainforest.

Koko met and befriended a number of celebrities over the years, too, including Barry White, William Shatner, and Leonardo DiCaprio. Robin Williams tickled her in 2001. Flea from Red Hot Chili Peppers tried to teach her to play the bass. When she appeared in an episode of Mister Rogers’ Neighborhood, one of her favorite shows, she signed to Fred Rogers that she liked his cufflinks.