"This is all about his attempts to become the personal representative of the estate," said David Bennett, Aretha Franklin's longtime attorney and lead counsel for the estate.
Owens, a University of Michigan administrator, has served as executor since Franklin's 2018 death, but matters were complicated last spring by the discovery of wills with conflicting instructions purportedly written by the late Detroit star.
At an August hearing, Judge Jennifer Callaghan authorized handwriting experts to assess the documents' validity. She also ordered Owens and Franklins' four sons to begin mediation and ideally hammer out distribution of assets.
The MGM-produced "Respect" began filming last fall and is scheduled for Oct. 18 release. As Kecalf Franklin acknowledged in his post, Hudson was handpicked for the lead role by the Queen of Soul.
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"Everything else is being done against our wishes," wrote Kecalf Franklin, who, at 49, is the youngest of the late star's four sons.
"The Franklin family (does not) support the movie that is in production!" he wrote.
But Bennett disputed the idea that Kecalf Franklin was a voice for all of Aretha Franklin's heirs.
"He does not speak for the family," the attorney said. "I know he doesn't speak for his brother Ted White or his brother Clarence Franklin. The grandchildren have absolutely nothing to do with this. What he's really doing is talking for himself."
Court filings this summer from White and Clarence Franklin backed Owens in her role as the estate's personal representative.
Kecalf Franklin's attorney, Charlene Glover Hogan, did not respond to a Free Press inquiry Tuesday.
At the August hearing — a contentious affair that revealed the family's hardening battle lines — Bennett defended Owens' work for the Queen of Soul's estate, including a deal for a Ron Howard-produced "Genius" dramatized life story and the theatrical release of "Amazing Grace," a gospel film that netted the estate $1.1 million.
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"I don't understand the purpose of trying to interfere with the estate earning money on the (MGM) biopic," the attorney said Tuesday of Kecalf Franklin's post. "How does it benefit anybody?"
Bennett said he was contacted by an MGM representative about the social media post and "they're not happy about it."
Regarding Kecalf Franklin's complaint that he's had no input on the film, Bennett said that "at no time, to my knowledge, have (the sons) asked to participate in or be in contact with" the movie's screenwriters.
Moreover, he said, the "Respect" story line zeroes in on an early period in Aretha Franklin's life.
"Odds are, Kelf Franklin either was not alive, or was of such a tender young age, that he wouldn't have direct knowledge of matters" in the story, Bennett said.
Although "Respect" production is underway, the estate continues to negotiate with MGM to formally authorize the film. While the studio could release the movie without such a deal, "there's a big difference between authorized and unauthorized," the attorney said.
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In his Facebook post, Kecalf Franklin also criticized the publication of "The Queen Next Door," a collection of images by Aretha Franklin's longtime personal photographer Linda Solomon. Echoing his complaint about the MGM film, the "core" family was not contacted for input, he wrote.
Owens penned the book's afterword. An October release party at the Detroit Institute of Arts drew guests including former Michigan Gov. James Blanchard, former Detroit Mayor Dennis Archer and former Pistons star Isiah Thomas.
"These are respectful and loving tributes," Solomon said Tuesday. "Without them, we cannot continue to share and respect the legacy of Aretha Franklin. We've got to continue to teach her legacy. If we don't, she'll fade away."