Paris & Prince Jackson Upset Over Conrad Murray's Attack Against Late Grandpa Joe

Joe Jackson is being branded as the "worst father in history" by son Michael's death doctor Conrad Murray. RadarOnline.com has exclusively learned that Paris and Prince Jackson are "furious" over his brutal attack against their late grandpa.

In a shocking new interview, the 65-year-old medic — who was found guilty and jailed for his role in Michael's death in 2009 — slammed the family patriarch, who died on June 27 at age 89 from cancer.

As reported, Murray claimed in an interview that Joe "chemically castrated Michael as a child via hormone injections to delay puberty and maintain his high-pitched voice."

He continued, "I would not shed a single tear for the passing of this cruel and evil man, Joe Jackson. It is said that only the good die young. I hope Joe Jackson finds redemption in hell," said Murray.

Needless to say, the already-divided Jackson clan are not taking Murray's words lightly!

"They have already contacted their lawyers and are willing to do whatever they need to do in order to silence Conrad Murray," the source told RadarOnline.com. "Paris gets so worked up over everything and Joe's death is bringing up a lot of pain for her and she can't believe how everyone is so intent on destroying him right after he died."

"Everyone knows that Michael had a lot of issues with his father. They all did," the source added. "But if not for Joe they would not have the luxuries in life that they have today."