Why is There an Ape Aboard the International Space Station?

It must get really boring in the International Space Station, so what does one do to liven things up a little? Ape suit!!

Astronaut Mark Kelly tweeted a video of his brother Scott Kelly dressed up as a gorilla and chasing his colleagues around the space station.

I'm not sure how much it would cost to launch that suit into space, but in my mind it was worth every penny!