The parents of Catherine Miller say they hope there will be a nation-wide search for their 29-year-old daughter, who disappeared more than three weeks ago.

John and Terry Miller met with reporters in Halifax on Friday, their latest attempt to keep attention focused on their daughter, known as Catie.

"We have no idea of where she is," said John Miller.

Police say Catherine (Catie) Miller has brown shoulder-length hair that she often wears in a ponytail, pierced ears and grey eyes. (Submitted by Halifax Regional Police)

Catie Miller last made contact with her family on July 15, when she sent her mother a text message.

She hasn't used her phone or social media, or accessed her bank account since, her father says.

"It’s as if somebody threw a light switch," he said.

The Millers doubt Catie intended to leave.

She had paid the power bill and had cable TV installed in her Windmill Road apartment. Her hair straightener, which she always used, was left behind. There was a cat with no food or water.

Catie also skipped an appointment on July 28 that her parents feel was important to her.

"The family is beginning to believe that she did not intend to go anywhere prior to her disappearance," said John Miller.

Catie had been separated from her husband for about 18 months. They had a working agreement for the care of their 3½-year-old son, her father says.

She doesn't have a car. Her last phone call was to Bluebell taxi on July 15. Her family believes she does not own a valid passport.

Nearly four weeks on, with little information to go on, the Millers want to broaden the search.

"If she left in a car, voluntarily or otherwise, after this length of time, we feel she could be anywhere in Canada. We therefore feel this search has taken on a national perspective," said John Miller.

Const. Pierre Bourdages, with Halifax Regional Police, says they've received several tips from Halifax and Ottawa, and from around P.E.I., New Brunswick and Quebec.

"But nothing yet that was actually a confirmed sighting," he said.

Earlier this week, family and friends handed out posters at the Natal Day parade, which attracts a large crowd.

They’ve also set up a Facebook page.

The Millers say they will hold a vigil in Grand Parade square on Aug. 12 if Catie is not found by then.

Police say there is no evidence to suggest foul play, but there is concern for the missing woman’s well-being.

Catie Miller is described as white, five foot eight inches, 130 pounds with brown hair and grey eyes.

Anyone with information is urged to contact police at 490-5020 or Crime Stoppers.