The 29-year-old Smiley, of Silverdale, and her son were en route from their Kitsap County home to her stepfather's house in southwest Washington when they vanished. Silverdale is about 16 miles west of Seattle.
"It's almost like she vanished out of thin air," said Chelsie Woodard, Smiley's stepsister.
The van Smiley drove was found Sunday, abandoned and partially submerged in water on a remote Puget Sound beach.
Investigators were talking to people who know Smiley or her son and those who may have met her as she drove through the back roads of Washington State on Saturday night. Her fiance, Robb Simmons said Tuesday that Smiley is a recovering alcoholic who relapsed last week, KING-TV reported.
Simmons said she had been under stress lately. He had been having health issues and fears he might have cancer, and suggested this past week that they get married, he added.
But he said he doesn't believe the relapse played any role in her disappearance.
"The idea she would stop and drink is not a realistic thing," he told the television station. "I do not see her doing that, I don't see her doing that, putting herself at risk, getting in trouble with the law, putting her son at risk."
Carie Tonovitz, of Silverdale, said in an e-mail Tuesday that Smiley was a good mother who was very wrapped up in her son's life.
Detectives say they're trying to learn all they can about Smiley's emotional state.
"I'm trying to be optimistic. I'm trying to be hopeful," Simmons told KOMO Radio on Tuesday. "I just want to hear that she's safe."
Anyone with information on Smiley and her son's whereabouts should call Thurston County Crime Stoppers at 360-493-2222 or the Thurston County Sheriff's Office at 360-786-5500.
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