Police are continuing to appeal for public assistance after the disappearance of a woman in Broken Hill last month.
Marilyn Grubb, 64, is believed to have left a property on Menindee Road about 50 kilometres from Broken Hill on December 30 before driving her car in an unknown direction.
Daughter Beth Ashton, 33, said there is a possibility Ms Grubb is in Sydney.
"We are just not sure which direction she has gone, my brother lives in Sydney, my sister lives in Dubbo, I am from Perth, and we have family across the Northern Territory and Adelaide," she said. "We are trying to narrow down a direction but it's very hard."
Ms Ashton also told the Herald how she missed a call from Ms Grubb, who is a mother of four and a grandmother of 13, on the morning of her disappearance, who was calling to wish her granddaughter a happy birthday.
Police have conducted a number of searches, as well as Ms Grubb's family hiring the use of a local helicopter service to search themselves, to no avail.
The family believes she packed a bag to take with her, and that she may have gone off the road either by accident or on purpose.
"She wasn't in the greatest state of mind, she's been through a lot this year," she said. "Anything is possible at this stage, she could have even had a medical episode."
Police believe Ms Grubb drove from the property near Broken Hill in a blue/grey 2005 Holden Adventra station wagon, with South Australian registration plates S048BON.
The family have asked everyone to keep an eye out for the number plates.
"We just want to know she's safe, she doesn't have to come home, we don't need to know where she is," she said. "She can just get in contact with police and tell them where she is and that she is safe."
Police and family are urging the public in the Broken Hill area to check CCTV and dash cam footage for sightings of Ms Grubb. The family has also set up a GoFundMe page to fund another helicopter search.
Anyone with information on the whereabouts of Ms Grubb is urged to contact police or Crime Stoppers.
Lifeline 13 11 14