Australian police are still investigating the crash, which also killed 50-year-old Craig Whittall, who was driving the other vehicle involved.
Ms Falkholt and her sister Annabelle were pulled from the crash, as the vehicles went up in flames, but her parents died in the burning auto, along with the 4WD's driver.
Jessica Falkholt's family were killed in a auto crash on Boxing Day.
Fighting for life in the Intensive Care Unit at St George Hospital, Jessica's family has been by her side ever since the accident and have been told by her surgeons that the actress' recovery is now a "waiting game".
The 29-year-old and her 21-year-old sister Annabelle were pulled unconscious from the wreckage of the crash, which occurred on the coast of New South Wales. The Daily Telegraph reports that Whitall had many previous driving infractions, including a nine-year ban and had at least 10 convictions for driving without a licence. Jessica has reportedly undergone several surgeries, including the removal of a kidney and part of her skull, and has been in a coma. The family was returning from Christmas holiday.
Police are now investigating the cause of the crash.
An autopsy may fail to determine if any drugs were in Mr Whitall's system due to his severe injuries and subsequent fire.
Jessica was born in Sydney and studied at the National Institute of Dramatic Art before landing her first acting roles.
Falkholt played Hope Morrison on the popular soap opera Home and Away, and the show paid tribute to her on Twitter with a simple message: "Rest in peace, handsome Jessica Falkholt". She then filmed a role in the U.S. film Harmony, which is set for release this year.
The family is now playing a "waiting game" on the condition of the actress, with doctors telling them it could be weeks or months before her recovery time is known. "Jessica is a most lovely person".