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Roo is one of the characters residing in the 100 Acre Wood, and the son of Kanga. He appears in Kingdom Hearts, Kingdom Hearts: Chain of Memories and Kingdom Hearts II. Whenever he goes out with his mother, he goes inside her pouch. Roo is never seen alone; he is always found with either Kanga or Tigger (whom he idolizes from their shared love of bouncing).
Roo appears in many of the mini-games in 100 Acre Wood. The games he shows up in are Tigger's Giant Pot, Pooh's Muddy Path, Balloon Bounce, and The Exposition. In Kingdom Hearts, he is a big help in the Bouncing Spot page area where he helps Sora by catapulting him into the trees to get special items or Rare Nuts for Owl and he helps Sora with advice with Tigger's challenges. He is voiced by Jimmy Bennett.
 Kingdom Hearts
Roo is one of Pooh's friends that he is looking for.
 Kingdom Hearts: Chain of Memories
Roo is one of Pooh's friends that must be found for Sora to complete the 100 Acre Wood.
 Kingdom Hearts II
Roo is seen with Kanga and Tigger and also helps Sora with the others find Pooh in the Spooky Cave.
Unlike Piglet, Roo's size does not prevent him doing the best of his ability. Roo is a playful, curious, happy-go-lucky joey who can be quite a handful at times. He has a strong determination as evidenced in time spent furthering his bouncing abilities. Roo loves to get himself in trouble, but always learns a lesson from his mistakes. Roo is amazingly optimistic and enthusiastic as shown in the search for Pooh. Roo has great admiration for Tigger, who he views as the epitome of bouncing and dreams of bouncing just like him someday.
Roo is a joey who's height is similar to Piglet's. Roo has light brown fur and an upturned tail. The pads of his feet are a light pink, along with the inside of his ears. He has beady, black eyes and thin eyebrows. He also has a small nose and black mouth. His only attire is a sky blue t-shirt that he wears all the time. Finally, Roo sports two strands of black hair on the top of his head.