Michael Jackson's children have become so close to his sister Janet in the wake of his death that they have started calling her "mama", according to the Mirror.

Though Michael's mother, 80-year-old Katherine, is legal guardian to the three kids, she is reportedly struggling to keep up with them.

A source close to the family told the Mirror: "Katherine does the best she can for those kids. But it's really Janet who has become the main force in their lives. They absolutely adore her.

Apparently the name "Mama Janet" was her own idea, as it was comfortable for the kids and would not upset her own mother.

The source added: "Janet is really careful not to step on her mother's toes because there has been a bit of a battle among the Jackson women over who should raise the kids.

"Janet is closest to 11-year-old Paris, who is delighted to have a mother figure in her life after years of only occasional contact with biological mum Debbie Rowe. Paris adores Janet and the two will talk for hours. Janet often visits around dinner time and cooks with the kids.

"A few weeks ago she took Paris on a trip to help pick out clothes for the new school year, even though she's educated at home."

Recent reports have suggested that both Michael's elder sisters, LaToya and Rebbie, are keen to take on the children when Katherine dies.

Since LaToya is reportedly convinced that Michael has been talking to his macaw, perhaps the kids would be safer with Janet.

Young Paris Jackson paid tribute to her father at his public send-off. We take a look back at the emotion of the evening...