I agree with Karen, ownership is not necessarily a concept that the heart recognizes.

Legally it is my sister who "owns" my cat Prema since she was the one who adopted from the local rescue shelter and her name appears on all the official documents. After only a couple of days though Prema decided that she would adopt me and would follow me around everywhere, therefore my sister had to leave her with me when she moved back to her own apartment! (Lucky for me... Prema is my little angel and I would not give her up for the world)