'I woke up randomly at 3am with a sense of dread. Hours later I got the call that still haunts me.'

Warning: This article discusses suicide and self-harm.

Matilda "Tilly" Rosewarne was a gentle, sensitive soul, with an infectious sense of humour.

She was the kind of child teachers adored; quiet, creative and kind-hearted, with a love of dance and art.

She was the apple of her mother, Emma Mason's, eye.

At the age of just 15, Tilly died by suicide after years of relentless bullying.

"It was a really hard time," Emma told Mamamia. "It was a very toxic time. I saw the chipping away of this really sweet, gentle and creative girl who just couldn't engage in her world."

Listen: I talk to bullied kids all day and one thing keeps coming up. Post continues below.

A relentless campaign of bullying.

Emma believes Tilly's gentle nature, whilst endearing, also made her vulnerable.

"She sort of attracted people that would easily push her around," Emma said. "Then it would all go very pear-shaped."

The bullying started when Tilly was just eight years old. It started as harassment at school before evolving into something more sinister online.

By Year 7, the relentless targeting had begun to take its toll on Tilly.

"She felt very socially isolated by the time she was in Year 7," Emma said.

Tilly was quiet, kind and creative. Image: Supplied.

The turning point came after a fake intimate image was created and shared of Tilly. The image spread like wildfire through their small town of Bathurst, in regional NSW, reaching hundreds, then thousands of students.

For a then 13-year-old Tilly, the humiliation was unbearable.

"The harm was so swift that within an hour, it was viral," Emma said.

The bullying started when Tilly was 8, and by the time she was in Year 7 had changed to encompass online bullying.

The online harassment continued throughout this period.

"We had lots of mental health engagement with psychologists and all that," Emma said.

Emma said she found evidence of Tilly's deteriorating state in her art books after she had passed; drawings and writings about death. They painted a picture of a girl who had lost all hope.

"I don't think writing about death and drawing about death makes you more positive about life," Emma reflected. "I think it's the opposite."

On February 14, 2022, two years after Tilly's first suicide attempt, Emma noticed something that made her uneasy.

Emma had taken her youngest daughter to Sydney for a medical appointment, leaving Tilly at home with her father, aunt and other daughter.

During their nightly FaceTime check-in, Tilly had a full face of makeup on at 9pm.

"In the back of my head, I thought it's 9 o'clock at night. Why have you got a beautiful face of makeup on? Like she had clearly just finished it and she said, 'I'm just bored,'" Emma recalled.

The next night, Tilly again appeared on their video call with perfect makeup, prompting Emma's sister to comment on it.

"She liked to practice makeup," Emma remembered. "You're kind of trying to keep your need to freak out just down to only 90 per cent."

At 3am on February 16, Emma woke suddenly in her Sydney hotel room, her heart pounding with inexplicable dread.

Matilda "Tilly" Rosewarne. Image: Supplied.

"I woke up at an absolute start," she said. "I couldn't get to sleep till probably about 12 o'clock and woke up jumping and thought 'what the hell, what the hell what's going on?'"

Hours later, at about 6am, as she was preparing to drive home with her youngest, her 13-year-old daughter called, screaming down the phone.

"I put my phone on speaker, which is something I will just regret forever, but I put it on, and I can just hear her screaming, saying 'Tilly's dead,'" she said.

Turning pain into purpose.

Within days of Tilly's funeral, Emma was already thinking about how to prevent other families from experiencing the same devastating loss.

Standing on her verandah, she spoke to a journalist about the urgent need for action on bullying and social media.

"How many more babies have to die? What is this? What are we gonna do about this bullying? What are we gonna do about social media? It's just so destructive for our children," she demanded.

That conversation sparked a journey that would take Emma from local government meetings to the halls of federal parliament, and ultimately to the United Nations General Assembly in New York.

In September this year, she addressed world leaders about the urgent need for social media reform.

Emma Mason addresses the Protecting Children in the Digital Age event at the United Nations headquarters in New York. Image: AAP/Lukas Coch.

Emma's advocacy has been instrumental in Australia's groundbreaking decision to ban social media access for children under 16; legislation she prefers to call "law" rather than "ban."

"I think ban says it's naughty, and you can get around it," Emma explained.

"We've changed the law because we've recognised a social harm. That is what a government's job is, to protect its citizens. It's government responsibility."

The law, which has inspired similar movements in New Zealand, the UK, and across the EU, represents a watershed moment in child protection.

"We are taking this to the world, and we're saying, you know what, we care about our kids, and we're going to do everything we can to protect them," she said.

Emma acknowledged the law won't be "perfect" in its initial stages.

"I think parents need help and that's what we want to know now. We want to know how we get our families through," she said.

"This is social heroin that we're going to turn off, and they need help."

The mother is resolved to protect other children from the harm of social media. Image: AAP/Lukas Coch

The mother also acknowledged the pain and all-encompassing grief her family will always live with.

"Suicide destroys families. It destroys marriages. It destroys everything. And I wouldn't wish it on anyone," Emma said.

"It breaks my heart every time I hear there's another child who has decided they can no longer cope."

But Emma refuses to let despair win, and now Tilly's name will forever be part of Australia's legislative history.

Her legacy lives on in every child who will now have the chance to grow up free from the toxic influence of social media, until they're old enough to handle it.

"Tilly's suffering mattered," Emma said. "It matters because it shows what the power of social media and the power of bullying can do to a human.

"We have to take the lesson of Tilly, and protect all the other Tillys.

"There are so many kids that we can save."

Feature image: Supplied.

If you or anyone you know needs to speak with an expert, please contact your GP or in Australia, contact Lifeline (13 11 14), Kids Helpline (1800 55 1800) or Beyond Blue (1300 22 4636), all of which provide trained counsellors you can talk with 24/7.

If you have been bereaved or impacted by suicide loss at any stage in your life, StandBy is a free service you can access on 1300 727 247.