Bleb joined Doc Johnson's Travelling Miracle Medicine Show as part of the transportation crew. Prior to that he served a stint in the U.S. cavalry and later worked as a lookout for a liquid corn farming enterprise. He was roped into these early jobs, but nevertheless took the opportunity to learn as much as possible from them. The skills he acquired -- pulling heavy loads, listening, and running at the first sign of danger -- have stood him in good stead and proven a valuable asset to Doc. When Doc and the medicine show came along, Bleb realized he had found his true calling. It is safe to say that Bleb chose Doc as much as Doc chose Bleb.
While other mules have come and gone over the years, Bleb has not only remained but worked his way up to First Assistant. He can count to 14, is smarter than he looks and should not be underestimated.