Guinness Heiress Honor Uloth, 19, Drowns in Swimming Pool During Family Party

Guinness heiress Honor Uloth drowned in a tragic pool accident during a family party earlier this summer in the U.K. Her family announced her death on Monday. The 19-year-old Uloth was the eldest daughter of Rupert Uloth and Lady Louisa Jane Guinness, and the granddaughter of Benjamin Guinness, the 3rd Earl of Iveagh.

Uloth was found unresponsive at the bottom of a pool during a party on July 31, according to the coroner's report obtained by PEOPLE. According to the report, Uloth left the nearby hot tub at about 11 p.m. that night to go swimming in the pool. "Shortly afterwards Honor was found unresponsive at the bottom of the swimming pool," the report reads. "Although the pool was lit it appears that Honor has either jumped or slipped into the pool and in doing so hit her head rendering herself unconscious. It is not clear what she hit her head on. There is no evidence that she suffered a medical event."

Uloth was rushed to St. Richard's Hospital in Chichester before she was taken to St. Thomas's Hospital in London. She died less than a week after the accident on Aug. 6. Her death was ruled an accident, with the cause of death listed as a hypoxic brain injury. There was an investigation into her death in August. According to the investigation, her brother, Rufus, 15, spotted Uloth in the pool. He dived in to try to save her. She suffered a broken shoulder and brain injuries, the report found, according to the Daily Mail.

"Police conducted an investigation... but no one saw what happened to Honor or knew how she came to be lying at the bottom of the pool," coroner's officer Geoff Charnock said during a hearing. He said police believe Uloth may have leaped from a rock and hit her head on it. Another police theory was that she slipped and banked her head, while a third theory was that she jumped into the pool and hit her head.

The Guinness family later sent a statement to The Daily Mail, confirming Uloth wished to donate her organs to save others' lives. They are "utterly devastated" by her death, adding that doctors have already found matches for some of her organs. "The doctors say that, with the matches they have found, it looks like she is going to help save four lives and seriously enhance ten more," the family said. Uloth was studying art history at Oxford Brookes University.

The Earl of Iveagh and the Guinness family, which founded the Guinness brewery company, has an estimated net worth of £906 million (about $1.19 billion). Uloth was the eldest daughter of Rupert Uloth, a former deputy editor of Country Life magazine, and Lady Louisa. "Honor was a diamond girl with a heart of gold whose ability to shine and bring lightness and joy was her life signature," Rupert told the Daily Mail.

"We will treasure so many memories about her: the sound of her singing and playing the piano…riding on the Downs and Commons in Sussex on the horses she loved; dancing and singing; trying to keep up with her off-piste in the Alps; sailing over her beloved Chichester Harbour where she spent so many happy weeks during her life; traveling the world with her and sharing her amazement and wonder," the Guinness family said in a statement to the Daily Mail. "Her last day was spent riding polo ponies in the morning, seeing friends on the beach in the afternoon, and enjoying an evening with close friends and family over a delicious al fresco supper. It was her perfect kind of day."