Gregg DeGuire / Getty Images 1 / 3
Gregg DeGuire / Getty Images 1 / 3

Daddy the Pitbull, Cesar Millan's right-hand-man and all-around favorite dog, has died, RadarOnline.com has learned.

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The canine was beloved by "Dog Whisperer" fans around the world, as well as Millan's family and the show's crew.

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Daddy's battle with cancer and his chemo treatments were featured on the National Geographic series. Fans of the show had come to love and respect the way Daddy worked as Cesar's partner in rehabilitating ill-behaved pooches every week.

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Daddy was 16 when he passed on February 19.

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Cesar & Daddy Helped Sort Out A Dog-Friendly Office