One Direction star Louis Tomlinson's sister Félicité has died at age 18.

One Direction’s Louis Tomlinson is grieving the sudden death of his sister Félicité Tomlinson, less than three years after losing his mother to leukaemia.

The 18-year-old died of a suspected heart attack at her London apartment on Wednesday around midday, The Sun reports.

The Instagram influencer and aspiring fashion designer reportedly collapsed in her apartment while in the company of a friend.

 

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Just getting used to posting pictures without my makeup done. Makeup is still fun and such a passion of mine but it’s nice to live my life now and not think that I need it, let’s stop all this negativity and judgement and all do what makes you the most happy and comfortable within yourself ????????

A post shared by Félicité Tomlinson (@felicitegrace) on Oct 20, 2018 at 11:27am PDT

That friend called emergency services, but paramedics could not resuscitate her and she was pronounced dead at the scene.

At this stage, Félicité’s death is “unexplained”. A post-mortem, including toxicology tests, will be carried out to determine what may have triggered her heart attack, The Sun reports.

The young woman’s death comes after she, Louis, and their siblings, lost their mother Johannah Deakin, who died of leukaemia in December 2016 aged 43.

 

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My mother looking gorgeous before the Brits earlier this year . I love you and miss you so much !

A post shared by Louis Tomlinson (@louist91) on Nov 18, 2016 at 11:59am PST

Louis was close to his sister Félicité – known to her friends and family as Fizzy – and was told about her death on Wednesday evening.

The former One Direction member and current UK X-Factor judge and solo artist was due to perform at Red Nose day fundraiser Comic Relief on Friday, but has reportedly pulled out.

He was going to perform his new song Two Of Us, which is a tribute to his late mother that includes the lyrics: “You’ll never know how much I miss you. The day that they took you, I wish it was me instead.”

 

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Family ❤️

A post shared by Félicité Tomlinson (@felicitegrace) on Dec 30, 2018 at 4:30pm PST

On social media last week Félicité commented on her brother’s song, telling fans:  “I cried my eyes out in the back of my Uber, but I loved the song filled me with hope.”

Louis shares his grief with his remaining siblings Georgia, Charlotte, Daisy and Pheobe, their step-father Dan Deakin, friends and other family members, as well as Felicite’s more than 1.4 million Instagram followers.

Fans have used her Instagram, as well as Twitter account, as places to express their grief, wishing her to rest in peace, and sharing comments like “my heart is broken”.

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