A close friend of a young mum critically injured when she was hit by a bus in Bali has revealed what happened in the moments before the collision, and has a message for those speculating online about the crash.

Alivia Jane Campbell, 28, sustained horrific injuries after her motorcycle collided with a truck.

Alivia Jane Campbell, 28, sustained horrific injuries after her motorcycle collided with a truck. Credit: Unknown/Facebook

Alivia Jane Campbell, 28, sustained horrific injuries after her motorcycle collided with a truck. Credit: Unknown/Facebook

A close friend of a young mum critically injured when she was hit by a bus in Bali has revealed what happened in the moments leading up to the collision, and has a message for those speculating online about the crash.

Alivia Campbell, 28 from the NSW Central Coast, is a critical yet stable condition in an induced coma in a Bali hospital after suffering severe brain trauma and a broken pelvis in the horror incident.

An update on her GoFundMe page from the mother-of-two’s overwhelmed but grateful friends and family has revealed hospital costs are “mounting fast” for her treatment and are expected to exceed $100,000.

This, plus a return flight with air ambulance or commercial medical escort could be up to $200,000, depending on her condition, they estimate

“Liv is due for a second major hip surgery this Saturday. Doctors are hoping they can bring her out of the coma in the next week,” the update read.

She is in a critical but stable condition in a Bali hospital.She is in a critical but stable condition in a Bali hospital. Credit: Facebook

Her friend Brooke van der Zwan, who was staying at a villa near to Alivia’s with another friend Reese Campbell — who set up the GoFundMe — has shed light on what happened in the moments leading up to the crash, and shut down conjecture suggesting Alivia had been drinking prior to the accident.

Ms van der Zwan said a quick errand to the shops to collect bottled water ended in tragedy for Alivia, who had only arrived on the holiday island late the night before.

She was riding a motorbike when it collided with a truck on Saturday about 11am.

“As she was pulling out, she was unfortunately hit by a truck. It was just a really tragic and unexpected accident,” Ms van der Zwan told the Daily Mail.

“Alivia and I share our location with each other on our phones, and she had been gone for longer than expected. So I checked it and saw that it showed she was at the hospital.”

Brooke van der Zwan with Alivia, below, and Reese Campbell, top right. Brooke van der Zwan with Alivia, below, and Reese Campbell, top right. Credit: Instagram

Ms van der Zwan, who has vowed to stay with her friend until she wakes from her coma, said Alivia’s father had flown over to Bali to be at her bedside.

“There was absolutely no alcohol in her system at the time of the crash. Everyone loves to assume that,” she said.

Ms van der Zwan has posted a series of videos of happier times that she shared with Alivia and her children on social media.

Addressing the online comments, alongside the post she wrote, “This is the person some of you are sitting behind screens talking about. A mum who loves her babies with everything she has and someone who means the world to the people around her.

“What we have had to witness as her best friends over the past few days has been one of the most traumatic experiences of our lives.

“Watching someone you love fight for their life is something no one should ever have to go through.

“And while we’re living through that, there are still people sitting behind screens spreading negativity about someone they don’t even know. People don’t seem to understand how damaging and cruel that is.

“Just remember, there are real lives and real families behind the names you type about.”