Katrina Sila dies in cement truck crash carrying two children on Hume Highway, Menangle Park, Sydney

The best friend and “sister” of a young mother who was killed in a horrific car accident along with her two children says the grieving husband has now been hit with huge funeral costs.

Katrina Sila, 34, and her two-year-old son, Kai Prahastono, were killed instantly when their silver SUV collided with a cement truck on the other side of Hume Highway near Menangle Park, in southwest Sydney, around 11:20 a.m. Monday.

Three-month-old Ivy was recovered from the wreckage in critical condition and airlifted to Children’s Hospital in Westmead.

She passed away early Wednesday morning.

The children’s father, Ian (Ilham) Prahastono, has spent the past two days watching his baby daughter live beside her hospital bed.

In the hours after the child’s death, Mrs. Sila’s “sister.” Diana Effendi called on community members to raise money for Mr Prahastono, who now has to pay for three funerals.

“We are calling on all our friends, family and wider community to raise money to cover funeral expenses following the tragic passing of… Katrina and their beautiful two [children]Mrs Effendi wrote on the GoFundMe page.

Katrina Sila, 34, pictured with her husband, son Kai Prahastono and daughter Ivy, who lost her fight for life on Wednesday

‘This beautiful family lives in South West Sydney and loves everything about this area, dreamed of raising their children here and called this community their forever home.

“Your prayers and any amount you can donate during this difficult time will be so helpful in easing the burden on Ilham and his family.”

It was revealed earlier on Wednesday that Mr Prahastono was at work at the time and was reportedly alerted to the crash by his Apple Watch on Monday morning, Seven News reported.

An Apple Watch feature detects when a serious car accident occurs and can help connect emergency services and notify emergency contacts.

Daily Mail Australia understands that both the grieving husband and his wife worked in finance.

Police said Ms Sila was on her way to the family’s Denham Court home in southwest Sydney when the tragedy unfolded.

It is believed she was attempting to make a U-turn from an emergency section on the Hume Motorway when she crashed into the truck.

The male truck driver, 48, was not injured and has since undergone a mandatory drug and alcohol test.

Katrina Sila (left) and her friend Diana Effendi (right) are pictured together when they were both pregnant with their children

Ian Prahastono (pictured with his wife Katrina) mourns the loss of his wife and two children. He was reportedly notified of the crash on Monday by his Apple Watch while he was at work

Police are investigating how the accident happened and will prepare a report for the coroner.

Investigators urged anyone with dashcam visibility nearby or anyone with more information to come forward.

The force of the collision sent the mother-of-two’s SUV engine catapulted 100 meters into the road, witnesses said, with a photo showing it lying on the side of the road.

Ambulance NSW Superintendent Mark Gibbs said paramedics faced challenging and confrontational scenes.

“It’s hard to imagine anyone surviving that wreck — such a tragic high-speed incident,” he said.

He also believed that the baby pod Ivy had attached probably saved her life at first.

“It shows how child seats work in such tragic circumstances,” Chief Inspector Gibbs said.

Pictured: Emergency services worked to get the trapped baby out of the car

The force of the collision catapulted the SUV’s engine 100 meters into the road

A family photo posted online in January shows Ms Sila and her husband smiling as they cradled their son and newborn daughter in their arms.

“We are heartbroken to announce the sad passing of Katrina Sila and son Kai… a loving daughter, mother, devoted wife, sister and friend to many,” said a family statement.

The family asked Mr. Prahastono to remain in everyone’s thoughts as he navigates such a “massive personal tragedy.”

Islamic prayer groups on Facebook posted a message on Tuesday announcing that Ms. Sila – a Thai Muslim woman – and her son had died in the crash and asked followers to pray for baby Ivy.

The latest tragedy comes just days after a father and his two children were killed on Saturday when their car crashed into a tree at Coutts Crossing, south of Grafton in northern NSW.

Lance Danks-Brown, 43, his son Kayden, 14, and daughter Sharna, 11, died at the scene.