Michael Jackson’s 13-year-old son Prince Michael restarted the murder investigation into his father’s death several months ago when the case stalled according to an Enquirer exclusive by offering to testify against Michael’s personal physician Dr. Conrad Murray.

Murray was charged with involuntary manslaughter Monday.

“It’s possible Dr. Murray would never have been charged if it wasn’t for Prince’s impassioned appeal to police a few months ago to ‘get justice for our daddy,’” revealed a source close to the investigation.

“The police were giving an update to some members of the Jackson family. When it appeared they could not offer a date when Dr. Murray would be arrested, Prince, who’d been listening outside the room, entered.

“He surprised detectives with an emotional statement. Prince told them ‘not to give up’ and said their father had told him and his sister Paris many times that ‘anything is possible if you want it hard enough and you work hard enough.’

“Prince even offered to testify against Dr. Murray because he said, ‘I was there – it’ll be in my memory forever.’

“The hard-nosed detectives were practically moved to tears. The investigation picked up – and Prince is to thank for that.”

A Jackson family friend added: “Prince is the only person, aside from the doctor, who saw what really happened – and he says he thinks that the doctor did something wrong, that he killed his dad!

“Prince says he saw blood on his father’s clothes, and there were times the doctor would not let him and the other kids in the bedroom to see their dad.”