Billy was bought by a circus when he was still a baby and arrived at the Sanctuary in 2004 as a young adult. He is very intelligent and extremely humanized. He sometimes has explosive attitudes and has a very individualistic personality – he doesn’t like to share his things. 

When he was still very young at the circus, he briefly lived with two chimpanzees, Tião and Monica, who also moved to the Sanctuary a few years later. But as Billy doesn’t have fond memories of his time at the circus, they didn’t get on well and so they didn’t live together at the Sanctuary. 

Despite his temper, he is affectionate and very playful. He loves seeing his reflection in the mirror. He’s very expressive, asks for what he wants with gestures and likes to point out the parts of his face when he’s looking in the mirror, identifying his eyes, mouth, teeth, etc.