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A belly rub or tummy rub is the act of gently touching a dog's stomach area. Numerous dogs enjoy belly rubbing, but not all of them. When a dog rolls on their back, it may be an indication that the dog wants a belly rub, however it is not always the case. A dog’s stomach is an immensely vulnerable part of their body. Some body language that indicates that a dog wants a belly rub includes vocalization, tail waggling, open (or squinty) eyes, relaxed and open mouth, while their body is wiggly and loose. If the dog kicks their leg or both legs during belly rub, it is completely normal, and the phenomenon itself is called a scratch reflex.