LOS ANGELES (AP) — “Heal the world. Make it a better place for you and for me.” So sang Michael Jackson in his mega-selling 1992 anthem for change.

Now the singer’s estate and Jackson’s mother could use a little healing themselves as they fight each other over the non-profit Heal the World Foundation, which claims it’s the successor to the pop star’s defunct charity inspired by the song. At stake in the skirmish are trademarks worth millions of dollars and a piece of Jackson’s legacy.

The dispute, which is playing out in a federal court in Los Angeles, is the latest example of the sometimes strained relationship between Jackson’s family and his estate, which has already earned hundreds of millions of dollars.

But the fight against the new incarnation of the Heal the World Foundation has also raised questions about which causes the singer would want to focus on if he hadn’t abandoned his charity to fight off allegations of child sexual abuse.

His mother, Katherine Jackson, left little doubt about her sentiments in a recent court filing: “It is not my desire, nor would it be the desire of my son Michael, to continue this lawsuit against Heal the World Foundation.”

Her attorney, Perry R Sanders Jr, said Friday that Katherine Jackson supports the charity but hopes that a more civil relationship between her and the estate can be restored. Sanders was hired late Thursday after Katherine Jackson’s former attorney publicly cast doubts about the authenticity of her filing.

“Bottom line — I am going to do anything in my power to try to tone down the rhetoric that has happened to date to the extent possible,” Sanders said.

Last year, Jackson’s mother and father joined Heal the World’s board of directors and placed their three grandchildren on a youth board. Jackson’s mother and his children were prominently featured on a recent Good Morning America story that also included footage of Heal the World giving a $10,000-donation to a shelter in Los Angeles.

It was a high-profile plug for an entity that, according to tax filings reviewed by The Associated Press, has done little fund-raising or charitable giving, but has fought to stake its claim to several Jackson-related trademarks and likeness rights that the singer’s estate maintains it should own.

Jackson’s estate wrote in a statement to the AP that the new Heal the World Foundation “has no relations to Michael Jackson’s charity that touched so many lives before becoming inactive several years before Michael’s death.”

Complicating Katherine Jackson’s involvement with the foundation is her business relationship with Howard Mann, a businessman who obtained some of Jackson’s recordings years ago. Mann, who is paying to defend Heal the World in court, is also being sued by the estate in a separate lawsuit that accuses him of infringing on estate copyrights.

The estate accused Mann of trying to secure Jackson copyrights for profit, which it said would deprive Jackson’s children of money they are owed.

Since Jackson’s June 2009 death, there at times has been an uneasy relationship between the Jackson family and the estate. Michael Jackson’s 2002 will calls for his mother and three children to receive 80 per cent of his estate, with the final 20 per cent designated for an unnamed charity.

Katherine Jackson had sought to challenge attorney John Branca and co-administrator John McClain’s authority to run the estate in 2009, but dropped the bid.

In the meantime the estate has worked to repair major financial damage incurred by Michael Jackson during his lifetime. The Thriller singer died more than $400 million in debt, but in the first 17 months after his death earned more than $310 million, court records show.

More than $9 million has been paid to and for Katherine Jackson and her son’s children, nearly $4 million of which went to pay off the family’s longtime home.

Jackson’s estate is hoping next week’s trial before US District Court Judge Dolly Gee will end Johnson’s efforts.