McDonald’s purple doll is called Milkshake Brother, also known as Slippery Dudu.
The name of McDonald’s purple doll is Milkshake Brother, also known as Smoothie. Milkshake Brother is a cartoon character owned by McDonald's. The huge, smooth and refreshing purple Milkshake Brother is Ronald McDonald's best friend. His character is open-minded, optimistic, enthusiastic, and always full of happiness and positive energy. His image is deeply loved by consumers and has become one of McDonald's representative images.