Prince’s family have filed a lawsuit against the late artist’s former doctor for wrongful death.

Read more: Legendary artist Prince dies at 57

According to ABC News, the lawsuit alleges that Dr. Michael T. Schulenberg—the physician who treated Prince just days before his death—failed to treat the musician for his opioid addiction.

The lawsuit states that Dr. Schulenberg “failed to appropriately evaluate, diagnose, treat and counsel Prince for his recognizable opioid addiction, and further failed to take appropriate and reasonable steps to prevent the foreseeably fatal result of that addiction. These departures from the standard of acceptable medical practice had a substantial part in bringing about Prince’s death.”

Attorney John Goetz claims the lawsuit, which was filed in Minnesota Friday morning, says the family’s original lawsuit against the hospital in Illinois will eventually be dismissed as they move forward with this new action in Minnesota.

“The Minnesota lawsuit is against all parties whom we now believe share legal responsibility for Prince’s death,” says Goetz. “But it is possible that we will identify and add other parties as we move forward with the case.”

Prince died on April 21, 2016, at his Paisley Park studio compound in Chanhassen, Minnesota, after collapsing in an elevator and being found unresponsive. His autopsy showed the death was due to an overdose of fentanyl, after taking a counterfeit Vicodin pill that had been unknowingly laced with the opioid.

Authorities have attempted to find the source for the counterfeit pills for the past two years, but since no source was able to be identified, no charges were ever filed.

In a 2016 interiew, Dr. Schulenberg told authorities he had prescribed the musician Percocet on two occasions under the name of Kirk Johnson, the musician’s one-time bodyguard.

“But I don’t do things like that,” Dr. Schulenberg told the Carver County Sheriff’s Department. “Actually, it is probably the first time I have done anything like that.”

Prince’s family are seeking $50,000 in damages with this lawsuit.