Being a few years younger than Stitch, Cookie seemed to help reinvigorate the older pup. And in return, he acted as a mentor of sorts for her. The two of them were as close as could be.
"They loved each other very much," Dufur told The Dodo. "Cookie would always egg him on so he would play with her and they would take care of one another."
Stitch and Cookie were so perfect together, in fact, that Dufur was able to feed them from the same dog bowl without worrying about them squabbling. Stitch, in his own way, had trained Cookie to eat only her half of the food provided, leaving the other half for him.