Coroners have revealed the cause of death for Félicité Tomlinson, the 18-year-old sister of Louis Tomlinson, the BBC reports.

Local coroner Shirley Radcliffe confirmed that Tomlinson died of an accidental drug overdose, calling the mixture of drugs in her system “the perfect storm.”

The publication reports that Cocaine, Xanax and Oxycontin were found in Félicité’s body.

The model was pronounced dead at her studio apartment in London in March after an ambulance was called and paramedics attempted to revive her.

At the time, it was reported that Félicité collapsed after suffering a heart attack.

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Family ❤️

A post shared by Félicité Tomlinson (@felicitegrace) on

The One Direction singer took to Twitter to thank fans for their support in the wake of his family’s tragedy.

“Just wanted to thank everyone for their lovely words over the past couple of weeks,” he wrote. “Back in the studio today to vocal something I wrote a few months ago. Sending you all loads of love x.”

Younger twin sisters Phoebe Tomlinson and Daisy Tomlinson both took to Instagram to pay tribute to their late sibling.

“Words don’t even begin to describe how shocked and broken hearted we all are,” Phoebe wrote. “You were my best friend, sister, motivator and person that could make me laugh until I cried. I’m lost without you and the thought of never seeing you again scares me like you wouldn’t believe. I will love you forever and ever and you and mama will have a place in my heart until the day I die.”

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Words don’t even begin to describe how shocked and broken hearted we all are. You were my best friend, sister, motivator and person that could make me laugh until I cried. I’m lost without you and the thought of never seeing you again scares me like you wouldn’t believe. I will love you forever and ever and you and mama will have a place in my heart until the day I die. Please tell me your watching over us and that you will always remember the way we all laughed together. Our memories will stay with me forever. We made so many. I remember me, Dais, Lotts and you all sleeping in the same room on two bunk beds and we’d chat all night about random things that made us giggle. You were the best at story telling. Mummy needed you and you desperately needed her. I’m so glad your together now and she has you to rub her feet in heaven like you used to. I pray that you’re in a better place now. We love you like you wouldn’t believe. Fly high my beautiful sister ????????

A post shared by PHOEBE TOMLINSON (@thephoebetomlinson) on

She went on to discuss some of her cherished memories with her sister.

“Please tell me your watching over us and that you will always remember the way we all laughed together. Our memories will stay with me forever. We made so many. I remember me, Dais, Lotts and you all sleeping in the same room on two bunk beds and we’d chat all night about random things that made us giggle. You were the best at story telling. Mummy needed you and you desperately needed her. I’m so glad your together now and she has you to rub her feet in heaven like you used to. I pray that you’re in a better place now. We love you like you wouldn’t believe. Fly high my beautiful sister.”

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this is the fourth time I’ve tried to write this. No words will come close to explaining how broken I am, once again. My precious sister. My heart is bleeding. I keep imagining and praying they have the wrong person. Not my sister, my best friend. it was only a few weeks ago that we were sat on the sofa bed at 3am drinking tea, eating French fries and chatting about the future. You told me about all your plans. We were excited. I pushed you away when you tried cuddling me, I thought I would have so many more chances to do that. I would cuddle you a million times over if you were still here, with me. Protecting me from this cruel world. I can still feel your arms wrapping around my waist and your lips kissing my head. I can hear your voice. I want to hold you, keep you safe. Tell you how much you meant to me and how much I adored you. I’m frightened without you. You’ve left me feeling alone. Mama needed you. i hope you are happier up there with her. make sure you don’t forget about us. keep us in your conversations. i have two angels now, watching over me. i can’t wait to make you both so proud of me.

A post shared by DAISY TOMLINSON (@the.daisytomlinson) on

Daisy shared a family photo from way back when and wrote: “This is the fourth time I’ve tried to write this. No words will come close to explaining how broken I am, once again. My precious sister. My heart is bleeding. I keep imagining and praying they have the wrong person. Not my sister, my best friend.”

“It was only a few weeks ago that we were sat on the sofa bed at 3am drinking tea, eating French fries and chatting about the future. You told me about all your plans. We were excited.
I pushed you away when you tried cuddling me, I thought I would have so many more chances to do that. I would cuddle you a million times over if you were still here, with me. Protecting me from this cruel world.”

Adding, “I can still feel your arms wrapping around my waist and your lips kissing my head. I can hear your voice. I want to hold you, keep you safe. Tell you how much you meant to me and how much I adored you. I’m frightened without you. You’ve left me feeling alone.”

Félicité’s untimely death came nearly two years after her mother, Johannah Deakin, died of leukemia at age 43.