Katherine Jackson's lawyer, Londell McMillan, says that Michael's mother wants "a seat at the table" in all matters involving her late son's estate.
McMillan says Katherine called him the day Michael Jackson died, and that she and husband Joe Jackson expressed "concern" over the estate of the deceased icon.
They then hired him to represent Katherine's legal interests.
McMillan says Katherine Jackson will not challenge the will (which leaves her 40 percent of the estate and guardianship of his three children), but as far as the executors are concerned, he says, "She deserves a seat at the table at a minimum."
McMillan would not say if Katherine merely wants to be a third executor or if she will challenge named co-executors John Branca and John McClain.
Sources connected with Katherine claim she already asked the co-executors to allow her to participate in the decision-making and her request was "rejected."
McMillan says neither he nor Katherine are pushing for Joe Jackson, with whom Michael had a contentious relationship and left out of his will, to be co-executor.
McMillan, who worked for Michael Jackson during the last 3 1/2 years of the singer's life, also has repped Katherine on business matters related to her son.
The attorney says that he remains "optimistic they can work things out, but I'm prepared to go the distance if Mrs. Jackson directs to do so."