The heartbroken parents of the two children killed by a car in Sydney yesterday have broken their silence.

Emergency services were called to the scene of the horrific crash at the intersection of Joseph St (Cumberland Highway) and Gilbert Street in Cabramatta about 3.15pm on Wednesday.

Police say the children, aged one and five, were treated by NSW Ambulance paramedics on-site before being taken to The Children’s Hospital at Westmead in a critical condition but they could not be saved.

The children have been identified as five-year-old Katherine and 14-month-old Harry.

Their heartbroken parents spoke on Thursday morning, saying they forgave the driver.

“I would like to say thank you for everyone ... I wasn’t there, thank you to everyone,” father Vundy Tha said, reported by 7NEWS.

“Even the driver, I forgive him already.

“Nothing can change, you know? Nothing can change, I couldn’t get my kid(s) back.”

Mother Sok Ram said she could not believe what had happened.

“Why did my kids die? I hope (the car) would hit me, not my baby,” she said.

Ms Ram had just picked up her five-year-old from school before the accident.

Katherine, in her first year of kindergarten, had won an award and was excited to get home.

A driver, a 56-year-old man who has since been arrested, reportedly struck the family as they crossed a road.

At the time, Harry was seated inside a pram.

Ms Ram was treated for minor injuries at the scene.

Less than 12 hours after launching, a GoFundMe for the family has raised more than $40,000.

In the description, organiser Patrick Te said the lives of “two beautiful children” had been “taken in a split second”.

“A mother not only lost a child — she lost both of her children, her only two children,” he wrote.

He said the family visited the site of the crash on Thursday morning, in an experience which left him lost for words.

Mr Te said the family was “incredibly grateful” for donations received.

“I can tell you that Sok and Vundy are deeply grateful and completely overwhelmed by the outpouring of love and support from this community,” he wrote.

He said that Ms Ram blamed herself for the accident.

“No amount of money can ever ease the pain she’s carrying or bring them back. She’s blaming herself, and I don’t think it has fully sunk in yet. My heart breaks for her. No one — not even your worst enemy — should ever have to endure something like this,” he said.

All funds raised will go towards supporting the family.

“I’ve created this fundraiser to help support this family who has been through the unimaginable,” Mr Te wrote.

“It doesn’t look like things will get any easier anytime soon — it’s a long road ahead, and they deserve all the help they can get.

Mr Te said the deaths were “extremely difficult to comprehend”.

“As a parent myself, I cannot even begin to fathom the long road ahead for both the mother and father,” he wrote.

“Regardless of who is at fault, their journey to recovery will be incredibly difficult.”

While an investigation into the crash remains ongoing, Mr Te said he would continue to provide updates as more information came to light.

“Please kiss and hold your kids tight. Cherish every moment, because time with them is never promised.”