Los Angeles  - Jaycee Duggard, the kidnapping victim who was kept 18 years in a suburban California back yard, bonded "like a little family" with her captor, her stepfather revealed in an interview published Monday.

"We had Jaycee for 11 years, and they had her for 18. After that long, you bond," Carl Probyn told the San Francisco Chronicle. "That's probably what kept her alive - the fact that they all bonded. It was almost like a little family."

Duggard's bonding with Phillip Garrido over the years would explain how she was able to work with customers at his printing business, many of who said she had never behaved strangely or given any hint of her harrowing past.

Probyn said Duggard is with her children, her mother, her sister and her aunt at an undisclosed location, where they are receiving help from counselors.

Duggard, and her daughters, 11 and 15, were kept largely in isolation by their captors Garrido, 58, and his wife Nancy, 54, without ever attending school or seeing a doctor. The two suspects pleaded not guilty Friday to assorted rape, kidnapping and conspiracy charges.

Probyn said he was told by Duggard's mother that his stepdaughter looks similar to how she looked at age 11, that she is an excellent mother, and that she and her daughters face a difficult adjustment.

The reunion was taking place as police continued to search Garrido's property in Antioch, California, and a neighbouring property where he had worked as a caretaker. According to the search warrant, they are looking for evidence in connection with an unsolved series of murders of women whose bodied were dumped close to a location where Garrido worked in the 1990s.

Garrido is alleged to have kidnapped Duggard in June 1991, pulling her into a car in broad daylight from the streets of her hometown in South Lake Tahoe, California. Police never suspected him despite his being a registered sex offender and even though neighbours complained of young children living in a ramshackle tent camp in the back of his compound.

Duggard, 29, was only discovered when a campus police officer became suspicious of the behavior of her two daughters when Garrido took them with him to a religious meeting he planned to conduct at the University of California, Berkeley. When he was summoned to a meeting the next day with his parole officer, he came with his victim and the two daughters he forced her to bear. dpa