Lori Hacking's (search) father is now expressing deep reservations about his son-in-law in his daughter's disappearance.

"To a certain degree I have to draw the line. I want my daughter back," Eraldo Soares told FOX News on Saturday after meeting with Mark Hacking (search) at the University Neuropsychiatric Institute (search), where the 28-year-old is hospitalized.

"If he knows anything I want him to come out and tell us, help us," Soares said. "If she’s not alive then I want to retrieve her body and give her a decent burial."

Mark Hacking has been called a person of interest, but not a suspect, in the case.

During a somber press conference Saturday, the pregnant woman's family pleaded with the public to continue the search for her.

"She’s my only daughter," Thelma Soares said. "Please help us find her one way or another."

She said pages and pages of leads have been turned over to police, who began using cadaver dogs Saturday in their search for Lori.

Meanwhile, the eyewitness who said she saw Lori Hacking stretching at a park Monday morning is now backtracking, saying chances are only 50-50 that the woman she saw was the missing 27-year-old, she told FOX News.

Douglas Hacking said Friday he asked his son directly about his daughter-in-law.

"I looked him in the eye, and I said, 'I need you to tell me if you had anything to do with Lori's disappearance,'" Douglas Hacking said. "I have to tell you that he looked me in the eye, and he said, 'No.'

"And I know a lot of you will say, 'Well, who can believe that?' But I want you at least to know that much of it."

Lori Hacking was reportedly five weeks pregnant when she disappeared Monday, just days before the couple was to move to North Carolina, where Mark Hacking had said he was going to attend medical school.

Mark Hacking had initially said his wife did not wake him up after coming home from an early morning jog, as usual, and never showed up to work.

Police confirmed Friday that Mark Hacking was at a furniture store buying a new mattress just before reporting to police that Lori was missing.

Earlier, the family confirmed Hacking had lied to them about North Carolina. He never graduated from college nor was he accepted to any medical school, authorities said.

Eraldo Soares told FOX News his son-in-law's past lies make it difficult to believe him now.

"He said 'I’d never hurt Lori,'" Soares said of his conversation with Mark at the hospital. But he said so with the "same face he used to tell me about school."

Soares said he has lost his faith in his son-in-law. "Now I don't believe him," he said.

Douglas Hacking has also confirmed that police found his son running naked early Tuesday at a hotel about a half-mile from the couple's apartment. He was taken to a hospital.

Lori Hacking's family insisted the focus of the case should be on finding their daughter. Mark Hacking remains hospitalized but has been available to investigators, Detective Dwayne Baird said.

Thelma Soares said she also visited briefly with Mark Hacking at the hospital on Friday.

"As I walked in, he was standing, and he put his arms out, and enfolded me in his arms. I just whispered into his ear, 'Mark, didn't you know that my love for you was not conditional upon you becoming a doctor?'" she said.

She said he wept but did not answer.

"It's just impossible for me to believe that Mark would harm Lori because he loved her so much," Soares told FOX News Friday. "This is a longtime romance" that started in high school.

Police removed several items from the couple's apartment Monday, but have declined to say what investigators took. Reporters saw paper bags, boxes and a box spring being removed.

Police also impounded a large trash bin from behind the apartment complex and took a swab Friday from a municipal plastic trash bin that had been left on a street by a neighbor outside the Hackings' apartment building the day Lori disappeared.

Also Friday, the only reported witness to see Lori Hacking on the morning she disappeared backtracked, telling KSL NewsRadio she no longer thinks the woman she saw stretching at a city park was the missing jogger.

Fox News' Carol McKinley, Claudia Cowan and The Associated Press contributed to this report.