BUFFALO, N.Y. -- The Buffalo Zoo celebrated a special birthday Sunday.

The zoo's baby gorilla Kayin turned one Monday, and the zoo invited visitors to join in a birthday celebration.

The party was held a bit before Kayin's actual birthday, which is Jan. 10.

Emily DeTine, a Buffalo Zoo gorilla keeper, said they celebrate each of the zoo's birthdays by decorating their enclosures with streamers and other decorations.

On Sunday, Kayin's birthday celebration included activities for Kayin, other gorillas and visitors.

Karin looked like he had a good time, he took it all in on his mother's back throughout the event.