However, one day Koko learned the hardest news when All Ball was run over on a logging road. Koko was so devastated that she expressed her sadness and grief to her trainer through Sign Language. She screamed the loss of her best friend and wept alone in her room after learning what happened to All Ball. The story was extremely touching. It gives us new insight into the depth of emotions that animals experience.
Koko has been trained to read sign language by the The Gorilla Foundation and understand more than 1,000 signs in American Sign language and approximately 2,000 words of spoken English. Koko used her linguistic skills to show her trainer that she wanted to have a kitten. Her request was then granted which gave her her very best feline buddy, All Ball.