Robert F. Kennedy Jr., Secretary of Health and Human Services, revealed new details regarding the 2019 death of his niece, Saoirse Kennedy Hill, stating that she died from an accidental fentanyl overdose. Kennedy shared this information in a social media tribute on the anniversary of her passing. He described his niece as "a luminous soul" who died at age 22.

Saoirse Kennedy Hill was found unresponsive at the Kennedy family compound in Hyannis Port, Massachusetts, on August 2, 2019. Toxicology reports at the time of her death indicated the presence of methadone, fluoxetine, norfluoxetine, diazepam, nordiazepam, and alcohol in her system. Fluoxetine is an antidepressant, while diazepam is used to treat alcohol withdrawal symptoms.

Kennedy's post, which included family photographs, was later deleted from his social media accounts. It is unclear if he was aware he was disclosing previously unreported details about the cause of death.

Saoirse Kennedy Hill was the daughter of Courtney Kennedy Hill and Paul Michael Hill. Her grandfather was assassinated presidential candidate Robert F. Kennedy.

Her death at 22 marked another tragedy for the Kennedy family, often referred to as the "Kennedy curse." This series of misfortunes includes the assassinations of President John F. Kennedy and Senator Robert F. Kennedy, a fatal car crash involving Senator Ted Kennedy, the death of Jacqueline Kennedy Onassis from cancer, the skiing accident death of Michael Kennedy, the plane crash that killed John F. Kennedy Jr., his wife Carolyn Bassette, and her sister Lauren Bessette, the overdose death of Robert F. Kennedy's son David, the drowning of Maeve Kennedy Townsend McKean and her son Gideon, the sudden heart attack death of Kara Kennedy, and the recent death of Tatiana Schlossberg, John F. Kennedy's granddaughter, from cancer.

Saoirse Kennedy Hill had publicly discussed her struggles with mental illness, depression, and anxiety. In an op-ed for her student newspaper in 2016, she wrote about her lifelong battle with depression and the pressures associated with her family name, describing bouts of sadness as feeling like "a heavy boulder on my chest."