The Lewis County Sheriff's Office is asking for the public's help in the search for 33-year-old Elizabeth Pham, who was last seen Saturday.
Her family says the Centralia resident, who has three children, may be suffering from postpartum depression.
The Washington State Patrol located her vehicle Saturday evening on southbound Interstate 5 near milepost 59 in Toledo, Washington. The vehicle was unlocked and the keys were inside.
Investigators believe Pham left her vehicle Saturday morning and walked to a truck stop, where she tried to hitch a ride with a truck driver headed to Redding, California. A truck stop employee stopped Pham and called for a taxi.
Pham asked the taxi to take her to Olympia, before asking to be dropped off at a Shell Station at exit 59. The driver described her behavior as "unusual and confused."
She didn't buy anything, according to the LCSO, but spent 20 minutes at the Shell station before walking to Beasley's restaurant and placing an order.
The last reported sighting of Pham was later in the day when a witness said she was sitting under the overpass at exit 59 beside the Cowlitz River.
"It's scary more than sad," said John Pham, Elizabeth's husband of 15 years.
He and the family fear Elizabeth Pham has been battling postpartum depression since the birth of their baby seven months ago.
"She's just disoriented, she doesn't know what she's doing sometimes," said Pham.
Elizabeth Pham's mother, Mary Stahl, said the family noticed Elizabeth started to get worse over the last week.
"She started being more out of character, confused and not making sense, then suddenly, she's back together and happy," said Stahl.
According to the sheriff's office, a fisherman located Elizabeth Pham's makeup bag downriver from where she was last seen and turned it into the Castle Rock Police Department.
Elizabeth Pham is described as a white woman with blonde hair and blue eyes. She is 5-feet-6 and weighs 122 lbs. Pham was last seen wearing a red or pink top, purple pajama bottoms and socks.
Anyone with information about Pham is asked to contact LCSO Detective Jeremy Almond at (360) 748-9286.
KING 5's Drew Mikkelsen contributed to this report.
