Prince's heirs are suing Walgreens and the Unity Point Trinity after he suffered a drug overdose just a week before he died.

Prince was 57 when he was found in an elevator at his Paisley Park estate on April 21, 2016. He died from an accidental overdose of the powerful synthetic opioid fentanyl.

About a week earlier, his plane made an emergency stop at the Quad Cities International Airport when he suffered from an opioid overdose and had to be revived by paramedics.

The wrongful-death lawsuit filed Friday in Cook County, Illinois, alleges that a doctor and pharmacist at Trinity Medical Center failed to appropriately treat and investigate Prince's overdose, contributing to his death.

Walgreens declined comment due to the pending litigation.

Spokesperson for Unity Point, Brian Boesen said via email, "UnityPoint Health is unable to comment on pending legal matters.”