In 1972,
Michael recorded the song Ben, for the film of the same title. The words appear to be about a deep friendship and there is no clue in the lyrics that it was written about a rat!
Michael saw the film Ben many times, waiting to hear his song and see his name in the credits on the screen. As a child,
Michael loved rats. At one point, his mother Katherine was horrified to see that he had thirty rats in a cage in his bedroom. He was passionate about the rodents until the day he discovered they were eating each other - as rats sometimes do. He was sickened by the sight and put the rat cage outdoors!
Taken from
Michael Jackson - The Magic & The Madness by J Randy Taraborrelli