MODESTO - Laci Peterson had picked out a couple of names for her boy, due the week of Valentine's Day, and had already outfitted a room with baby toys and blankets.

But the nursery and the rest of the home where Peterson lives with her husband, Scott, have been sealed off as investigators search for clues into the Christmas Eve disappearance of the 27-year-old woman.

Scott Peterson told investigators he last saw his wife at 9:30 a.m. Tuesday, when he was on his way out to go fishing at the Berkeley Marina. She was going to shop for that night's holiday dinner and walk their golden retriever, McKenzie, police said.

When Scott Peterson returned at 4:30 p.m., his wife wasn't there and McKenzie was in the back yard. His wife's Land Rover was parked out front, and her purse was in the house.

While authorities said they have no evidence to suggest Peterson's husband was involved in the disappearance, they sent two detectives to Berkeley to check out his story. They called in FBI agents to spray a chemical that reveals blood stains and other evidence, but Modesto police would not discuss if anything was found in the house.

Police also searched the Petersons' computers and vehicles, and planned to serve a search warrant at the couple's storage facility where a boat was kept.

Laci Peterson's family was adamant that her husband is not involved.

"She and Scott are so much in love,'' Sharon Rocha, Laci Peterson's mother, said Friday at a news conference. "They tried for a long time to have a baby, and this was just the center of her world: to have her husband and her baby.''

In fact, Rocha said, her daughter and son-in-law have a relationship that people envy. The couple met at Cal Poly-San Luis Obispo, family members said, and married soon after graduating in 1997.

Laci Peterson got a bachelor's degree in ornamental horticulture and worked as a substitute elementary teacher, relatives said, and Scott Peterson is manager of a fertilizer company.

The couple bought their three-bedroom home two years ago, neighbors said, and liked to do yard work together and play with the dog. They threw pool parties, the neighbors said.

"I have never, ever seen them fight or heard one argument,'' said Amie Krigbaum, who lives across the street.

Rudy and Susan Medina, who live next door to Krigbaum, said they returned home Thursday to find their back door kicked in and some electronics stolen.

Sgt. Michael Zahr, who is supervising the investigation, said Friday there is no indication of a connection but police will look into it.

Karen Servas, the couple's next-door neighbor, said she was pulling out of her driveway about 10:30 a.m. the day Laci Peterson disappeared and found the retriever standing in the street. As she led him back to her neighbor's house, she saw the side gate open and figured he had just wandered out as he had previously.

When Scott Peterson found out later that Laci was not home, he called friends and relatives to try to find her. The family reported her missing at 5:45 p.m.

Other people told police that they thought they had seen Laci Peterson walking in East La Loma Park, two blocks from her home, where she walks daily.

But a bloodhound led police in the opposite direction, officials said. The dog led its handler around the corner, onto Yosemite Boulevard west and then south to near the E&J Gallo Winery. Police sifted through nearby dumpsters and contacted landfill operators but found nothing.

Zahr said Friday that authorities have no solid reports of sightings of Laci Peterson and don't know if foul play was involved. They combed La Loma Park three times, and the couple's home Thursday and Friday.

"Hopefully, we'll find her safe and sound,'' said Zahr.

Volunteers set up a headquarters at a local hotel and fanned out across Modesto, handing out fliers with Peterson's photo. Relatives and friends of Laci Peterson, and the Carole Sund-Carrington Memorial Reward Foundation, have put up a $125,000 reward for information about her whereabouts.

Peterson's mother, Rocha, pleaded Friday for her safe return. "Whoever has her, please, please let her go,'' she said.

Peterson's younger sister, Amy Rocha, said her sibling is sweet and outgoing -- and a "huge part'' of their family.

"It's really, really hard,'' she said, standing in front of her sister's 1940s home, which was cordoned off with crime scene tape. "We have no ideas, no clues, nothing.''