Tributes are flowing following the death of actress Jessica Falkholt today, more than three weeks after a crash which killed her mother, father and sister.

Messages of sadness and devastation have been left on social media, with co-stars farewelling “wonderful Jess”.

Ms Falkholt, a former Home and Away star, was critically injured in a head-on crash near Ulladulla, New South Wales, on December 26.

After fighting for life in St George Hospital for more than two weeks, Ms Falkholt’s life support was switched off late last week.

The Home and Away star has died today, six days after her life support was switched off.

The Falkholt family. (Supplied)

The 29-year-old died at 10.20am this morning, the hospital confirmed in a statement.

"On behalf of the family of Jessica Falkholt, St George Hospital has been asked to advise the media and the community of Jessica’s passing today at 10.20am," the statement read.

"Jessica passed away from serious injuries sustained in a motor vehicle accident on December 26."

As news spread of Ms Falkholt's death, the actress's colleagues shared messages of grief online.

“Farewell wonderful Jess,” Home and Away star Pia Miller posted on Instagram.

Fellow co-star James Stewart farewelled Ms Falkholt on his social media fan page.

“Such a beautiful and talented soul – taken so soon and so tragically,” the post read.

“May you now rest in peace alongside Annabelle, Lars and Vivian.

“Sending my deepest sympathy to the extended Falkholt family and friends.”

Ms Falkholt's agents have expressed their deep sadness following her death.

“It’s clear that Jess was at the beginning of a stellar career,” Lisa Mann said in a statement.

For Belinda Maxwell, Ms Falkhot’s legacy is encompassed in her email sign-off.

“Jessica always closed her emails to me with the Greek expression, Philonexia!” Ms Maxwell said.

The expression means hospitality, but for Ms Maxwell, extends deeper.

“Philonexia also encompasses a generosity of spirit, something Jessica had in abundance.”

The Nine Network paid tribute to Ms Falkholt, who was to star in the broadcaster's new crime thriller Bite Club .

"Everyone at Nine is saddened by the tragic loss of the Falkholt family," the statement read.

"Jessica only worked with us briefly on Bite Club but she was clearly a young actress to watch with great possibilities ahead of her.

"No doubt her family and the broader community will be suffering today and we send our sincere condolences to them. RIP Jessica."

Ms Falkholt's death comes after hundreds of mourners gathered in Sydney’s inner-west on Wednesday last week to farewell her parents, Lars and Vivian, and sister, Annabelle.

Vivian's younger brother, Paul Ponticello, opened his words of remembrance in St Mary’s Catholic Church, Concord, by thanking police and paramedics, before talking about Lars and Vivian.

"Lars adored his girls, and was never happier when he was with them," Mr Ponticello said.

Hundreds gathered at St Mary's Catholic Church in Concord on Wednesday to farewell her parents, Lars and Vivian, and sister, Annabelle. (9NEWS) (9NEWS)

"We take a little comfort, in knowing they will be together.

"Their lives on this earth, ending on a highway, makes absolutely no sense."

Lars and Vivian Falkholt died at the scene when their car collided with a four-wheel drive on the Princes Highway.

Jessica and Annabelle were pulled from the wreckage of the car before it burst into flames.

Annabelle was critically injured and died days later on December 29.

Jessica and Annabelle were in the car when the crash occured on the NSW south coast.

The driver of the other car, Ulladulla man Craig Anthony Whitall, 51, was also killed in the crash.

Mr Whitall was reportedly returning home from a methadone clinic in Nowra at the time of the collision. In a funeral notice, Lars, Vivian and Annabelle were described as a “dearly loved and cherished".

"The ones who love us never really leave us, you can always find them in here," Anabelle’s best friend Brittany Macchetta told the service.

The Falkholt family is asking for donations to children’s charity Redkite in lieu of flowers.