DURHAM, N.C. — The Durham Police Department has changed the status of a missing woman's case to a murder investigation.

"It's scary," said Christopher Sutphen. "But I still keep the hope alive that my mother will come home."

Said Darren Sutphen: "You don't want to assume the worst. You want to keep your spirits in a positive direction."

In an interview with WRAL's Julia Lewis at the TV station on Thursday, Sutphen's sons described Sutphen as energetic and independent.

"My mom lived life by a different set of rules," Robin Sutphen said.

Janine Sutphen married husband Robert Petrick less than two years ago.

"Our impression was he made our mother happy," Christopher said.

The sons admitted that they knew little about Petrick, who has a long criminal history, much of it fraud.

"A lot of the stuff that's been reported about him is news to us," Christopher said.

Police charged Petrick on Monday with three counts of obtaining property by false pretenses and three counts of uttering forged instruments. They have not called him a murder suspect.

"I can't comment on any of the findings," said police spokesman Norman Blake.

WRAL has learned there are indications the couple was involved with pagan worship. But investigators won't say if that has anything to do with Sutphen's disappearance and possible murder

For the fourth day in a row, investigators searched the couple's home Thursday. Investigators were being meticulous, even taking apart the plumbing.

They have refused to talk about what they're looking for, or what they've found, saying only that they don't want to compromise their investigation.