(CNN) When legendary singer Aretha Franklin died, she did not have a will or trust. Her four sons have filed a document listing themselves as interested parties, reports say.

Franklin died last week from advanced pancreatic cancer. She was 76.

In addition to her sons' filing, Franklin's niece has asked the court to appoint her as a personal representative of the estate, the Detroit Free Press reported. It said under Michigan law, if an unmarried person dies without a will, his or her assets are divided equally among any children.

Franklin's lawyer has represented her in entertainment matters for nearly three decades, and told the paper that he constantly asked her to do a trust, but she never got around to it.

"I was after her for a number of years to do a trust," Los Angeles attorney Don Wilson told the paper. "It would have expedited things and kept them out of probate and kept things private."

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