Burrito and Negra have an interesting relationship. She seems genuinely afraid of him at times and will hide in the front rooms when he is displaying. And if there is excitement in the group, she will give him a huge submissive greeting (she will grunt loudly and present her rear end to him) as if to say “don’t take it out on me, please!”

But they also spend a lot of time grooming together, and once and a while Burrito can get Negra to laugh. Of course, he has to play Negra-style (calmly and slowly, laying down if possible), which is a stretch for Burrito. Take a look (FYI – the hissing sound you hear is me moving the pneumatic doors to let the chimps in for lunch):