NELSON COUNTY, Ky. (WDRB) -- No one has seen Crystal Rogers since July of last year. 

While the Nelson County Sheriff's office hasn't made any arrests, her longtime boyfriend Brooks Houck has been named as a suspect in her disappearance. 

Officials want Houck's grandmother to testify before a grand jury as they continue to work the case, but she's refusing to talk. 

That's what led to a hearing Wednesday, where prosecutors asked to postpone because of a recent grand jury hearing. 

"There was a possibility of some additional evidence that would have some bearing on this particular case," Commonwealth's Attorney Terry Geoghegan said.

The Commonwealth's Attorney's office says it now needs more time to decide what questions to ask Anna Whitesides. 

The subpoena order states her car may have been used to dispose of a body, subsequently cleaned and sold in an attempt to prevent the commonwealth from obtaining evidence from it.

"I think she knows something," said Sherry Ballard, Rogers' mother. "Why would she want to plead the fifth amendment? I'm sorry, but I'm not taking up for her. She might be old, but she's old enough to know better."

Whitesides' attorney says his client is invoking her fifth amendment right to protect her innocence, and that she's been treated unfairly. 

"(She) cooperated with the authorities twice, submitted to interrogation voluntarily," her attorney, Jason Floyd, said. "She showed them where to get the car and then was called a liar."

While Brooks Houck wasn't in the court room for his grandmother's hearing, he was at the courthouse Wednesday. He declined to comment. 

The hearing was pushed back to late-July.

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