Louis Tomlinson's sister Félicité died after accidentally overdosing on drugs.

As previously reported, the former One Direction singer's sibling was found dead in her London apartment in March from what was believed to be a heart attack. However, now her official cause of death has been revealed. According to a coroner, the 18-year-old died after taking a "perfect storm" of OxyCodone, Xanax and cocaine.

"I think the most appropriate conclusion would be a misadventure. This was an individual who took drugs voluntarily and has succumbed to the side effects of those drugs accidentally," Dr. Shirley Radcliffe said (via The Telegraph). "To some extent, I'm sure she knew the risks she was taking, but I do not think this was a deliberate act to end her life."

Though Louis never publicly addressed Félicité directly, he did share a message with his fans via Twitter in April: "Just wanted to thank everyone for their lovely words over the past couple of weeks. Back in the studio today to vocal something I wrote a few months ago. Sending you all loads of love x."

Félicité’s tragic death followed the death of her and Louis’ mother Johannah Deakin, who passed away from Leukaemia in 2016 at the age of 43.

Stars We Lost in 2019