Could this be diabetes?.....

Dear Karen - A friend of mine has swelling from the ankle to the knee on his leg. It started with joint pain in the knee (not the foot) and then a few days ago his ankle swelled up pretty big, and then it went up the leg to the knee. I was wondering if that was a symptom of diabetes. His mother and father both had diabetes. Plus, could you tell me what The Master Cleanse actually is? and how to make it. thank you. Joy