Sunny's new little sister, Rosy, is getting her paws into everything. When Rosy takes Sunny's favorite toy, Mr. Bunny, and loses him, Sunny is barking mad.
But when Rosy sets off on her own to find and rescue Mr. Bunny, Sunny starts to worry. Rosy's never been outside by herself before. Sunny will have to gather all the canine courage she has and go after them -- before Rosy and Mr. Bunny are both lost fur-ever!