In 1999, a kitten appeared in the yard of an elderly Massachusetts couple, and it was so small that Wallace and Ann Collito at first thought it was a rat. The Collitos believed that someone had thrown the black-and-white kitten over the fence into their mobile home park and they worried about its welfare until they noticed the cat’s unlikely caretaker, an American crow.

The Collitos watched in amazement as the crow took the kitten — whom they’d named Cassie — under its wing and began feeding it worms and insects. They couldn’t believe their eyes as they watched the crow they’d dubbed Moses feeding Cassie, protecting her from other animals and cawing to keep her out of the street. They knew no one would believe the remarkable tale unless they had proof, so they began filming and photographing the playful kitten and its watchful winged guardian.

Eventually, the Collitos were able to coax Cassie indoors with cat food and she spent her evenings enjoying the luxuries of indoor cat life, but every morning at 6 a.m., Moses would peck at the screen door looking for his friend, and Wallace and Ann let Cassie out to play. The unlikely friends spent hours frolicking and wrestling outside, and the Collitos filmed the playful pair’s escapades for five years until one day Moses quit showing up. American crows live only seven to eight years in the wild, so it’s thought that Moses passed away.

Ann Colito died in 2006, but Cassie — who’s now 12 years old — still lives with Wallace in their Massachusetts home, and Cassie and Moses’ story will continue to touch lives and teach lessons about friendship for years to come, thanks to a new children’s book by Lisa Fleming. The 48-page book, “Cat and Crow: An Amazing Friendship,” shares the story of Cassie and Moses’ special bond and includes newspaper clippings and photographs of the two. It was released on Oct. 16, which is National Feral Cat Day.

Check out this amazing video of Cassie and Moses above.