Diana Ross promised pal Michael Jackson she’d watch over his kids before the King of Pop died in 2009, and Ross has kept her vow!

“Diana admits that Michael’s kids are a ‘constant concern’ for her,” a Jackson family insider said.

While Michael made his elderly mom, Katherine, 86, the legal guardian of Prince, Paris and Blanket, he made his idol Diana promise to keep an eye on them, too.

So now, according to the insider, the Supremes songbird, 72, is desperate to get volatile Paris, 18, professional help and steer Prince out of trouble!

The superstar is “especially” concerned about Paris, who cut her wrists and took an overdose of Motrin in a failed suicide attempt in 2013.

“Diana really believes Paris needs to be in long-term therapy because she’s never really come to terms with her feelings about her father’s death,” the source said