Michael Jackson wrote a Simpsons song

Michael Jackson famously appeared in the 1991 episode 'Stark Raving Dad', in which he voiced the character Leon Kompowsky, a psychiatric patient who believes he is the King of Pop.

The episode culminates with Bart and Leon penning and performing the song 'Happy Birthday Lisa' for Bart's younger sibling to make amends for his earlier snub of her special day.

But did you know that this wasn't Michael's first foray in to 'The Simpsons'?

A year earlier, the album 'The Simpsons Sing the Blues' was released which contained the hit single 'Do the Bartman' which was co-written and co-produced by Jackson, who also provided backing vocals, although he was not credited.

In 1998, Matt Groening admitted that the King of Pop did indeed co-write the song with his friend Bryan Loren, but couldn't receive a credit due to contractual issues.