Lenna was just 10 or 11 years old when her mother began a relationship with Cary Stayner, a maintenance worker at the Cedar Lodge right outside of Yosemite National Park.
Her mother was a waitress at the California lodge in 1998 and Stayner lived in an apartment above the restaurant. Lenna said that at the time, Cary Stayner, in his 30s and handsome, appeared "safe" to her, her mother and younger sister.
He brought the girls illustrations he'd drawn himself and bought them a new Beanie Baby, a popular toy in the '90s, each time he'd see them, she said. Lenna, who asked that ABC News withhold her last name, said he also taught the two how to dive.
"He would show us how to point your toes or how to put your arms forward and dive perfectly into the pool," she told ABC News' "20/20" in an exclusive interview. "My sister and I both wanted to be the best at it. It feels like it was so long ago that you forget that it even happened and feels like, almost like a dream or ... a movie that you watched."
Watch "20/20's" full story, "The Black Sheep," TONIGHT at 9 p.m. ET on ABC
That dream ended for Lenna in 1999, when she learned from authorities that Cary Stayner was not only responsible for the brutal slayings of four women in and near Yosemite that terrified residents and tourists, but that he'd also tried three separate times to kill her and her family.
"It's very disturbing. I see two little girls, very innocent and very pure and very much so loving towards this man that wanted to do some horrible things to us," Lenna said. "He was right under everyone's nose. The entire time he was right there!"
Cary Stayner comes to Cedar Lodge
Cary Stayner had a tough childhood before he made his move to Cedar Lodge, where he'd eventually unleash a rage that had been simmering for years, according to people close to him.
In December 1972, his 7-year-old brother, Steven Stayner, was abducted in Merced, California, by pedophile Kenneth Parnell and accomplice Ervin Murphy. For seven years, Steven Stayner lived with Parnell, moving from one city to another, as the man sexually abused him.
The Stayners and law enforcement launched a massive effort to find Steven Stayner.
"Cary was very upset. I heard stories about him going out and wishing on a star, that his brother would come home. I believe he was supposed to have been with his brother. So I believe that there was some guilt with Cary on the fact that maybe he felt a little responsible," said childhood friend Mike Marchese in 1999.
Cary Stayner also wore a hat because he compulsively pulled his hair out.
"Cary started acting wildly inappropriately towards females. He exposed himself -- to one of his sister's friends," said magazine writer Sean Flynn.
"It seemed as though he had a compulsion with trying to get close to women or be sexual with them. But he was unable to develop any sort of interpersonal relationships with any women," said TV reporter Ted Rowlands.
More than seven years later, when Steven Stayner was 14, he and Parnell were living in Manchester along the coast of Northern California.
During this time, Parnell kidnapped a 5-year-old child in Ukiah, California and held him captive for two weeks before Steven Stayner escaped and took the child to the police. Steven Stayner was eventually reunited with his family and hailed as a hero. He made some money consulting on a TV film written about his horrifying ordeal and got a reward for rescuing the 5-year-old boy.
Parnell was convicted on kidnapping and false imprisonment charges. He was sentenced to seven years in prison but only served five -- less time than he held Steven captive.
But, at the age of 24, Steven Stayner, by then a husband and father of two, was killed in a motorcycle crash. Not long after Steven Stayner died, Cary Stayner's uncle was fatally shot in a home the two men shared.
"Steven's dead. Uncle Jerry's murdered. This rage is starting to bubble up. Cary has a couple of nervous breakdowns. One was fairly violent," Flynn said. "They got him to a mental health center, but he left. He was there for a couple of hours."
Cary Stayner became a lost soul. After bouncing around to different places, he finally settled down in Yosemite.
"Cary still didn't talk to anyone about Steven. Whatever damage that had [been] inflicted on Cary, I think he kept to himself. The obvious question is whether what happened to Steven caused Cary to do what he did," Flynn said.
When Cary Stayner was in his 30s, he drove his car -- a 1972 pale blue International Scout -- to El Portal and got a job as a handyman at the Cedar Lodge. The rustic lodge was just 7 miles outside the gate of Yosemite, where he sought refuge and got high on marijuana. He was also convinced that he'd seen Bigfoot while out in the woods.
"He couldn't wait to tell people about his personal experience driving through an area known as Foresta and Bigfoot leaping out of the woods in the dark of night and then scurrying back in, never to be seen again," crime journalist Pat Lalama said.
'A big teddy bear'
In February 1999, Carole Sund; her 16-year-old daughter, Juli Sund; and friend Silvina Pelossa, an exchange student from Argentina, were staying at the lodge. The trio was visiting colleges and enjoying Yosemite.
Cary Stayner had decided the day after Valentine's Day would be the day he killed Lenna and her family. However, his plan was foiled when he saw another person on the grounds where they lived, according to Jeff Rinek, a former FBI agent.
Instead, Cary Stayner returned to the Cedar Lodge and eventually turned his attention to the lodge's 500 building where the Sunds and Pelosso were staying.
"As I walked, there was a red car in the 500 building all by itself. The window was open, the curtain was open, and I can see inside that there was two young women and the mother and no man," Cary Stayner said in his 1999 taped confession, obtained by ABC News.
After gaining access to their room -- lying to Carole Sund about a leak in an upstairs room -- Cary Stayner strangled the mother and sexually assaulted and then killed Juli Sund and Pelosso. Carole Sund and Pelosso's bodies were found in the trio's burned-out rental car a month after they were reported missing. Juli Sund was found later that month after Cary Stayner anonymously sent a map and note to authorities, telling them where to find her body.
But when authorities went to Cedar Lodge to conduct interviews and spoke to handyman Cary Stayner, they were unaware he was the killer.
"He just didn't set off any alarm bells," said former reporter Christine Hanley. "He even told them a story about Steven (Stayner). At one point, he was even the guy opening all the rooms for the FBI to gather evidence."
He continued working at the lodge and living on the premises. Lenna said he was like a "big teddy bear" toward her and her sister.
"He was just our friend. I loved Cary. My sister and I adored him. ... My sister and I would be walking up the driveway and we’d see Cary Stayner coming up in his Scout, and jump in the truck and he’d give us a ride up to our house," she said.
Police eventually arrested two brothers with criminal records and wrongly accused them of the crimes. Then, in the summer of 1999, Joie Armstrong, a 26-year-old woman running educational programs at Yosemite for children, was reported missing by her friends and later found decapitated in the park.
Cary Stayner kills his fourth victim
The day Armstrong disappeared, Cary Stayner was driving his car to Foresta when he saw the young woman. She was packing her car as she prepared for a trip.
"I was just over there throwing rocks in the creek and just happened to notice her walk out again and again. It seemed like she was alone," he said during his taped confession.
He held her at gunpoint in her cabin as he bound her with duct tape and then forced her into his car. As he was driving, he said, she fell through the window of the vehicle and started running. Cary Stayner caught up with her and slit her throat.
"This was supposed to be easy for Cary. This was, you know, his fantasy was to, that nobody's supposed to fight back. And she did," Flynn said.
After Armstrong was reported missing, authorities went to her cabin and found debris -- broken sunglasses as well as a red mechanics hat -- and tire tracks.
"Cary Stayner left behind a boatload of evidence, and he knew it. Unlike the first three murders, where he left virtually no evidence, he knew that he had left a very easy trail for investigators," Rowlands said.
A witness had also identified Cary Stayner's vehicle as being on the road where Armstrong lived around the time of the murder, so authorities went searching for him. He was eventually apprehended at a nudist colony two hours north of Yosemite.
Speaking to the FBI, Cary Stayner admitted to killing Armstrong and the three women at Cedar Lodge but he also caught agents unaware, telling them about Lenna and her sister and mother.
"I could not believe what I’d just heard," the FBI's Rinek said. "I was literally trying to get my mouth going to hear that again to make sure I had heard what he said."
Lenna's family learns about Cary Stayner
Lenna said she could remember one occasion in which Cary Stayner had made her feel uncomfortable. They were at the Merced River, she said, when he started removing all of his clothes.
"I remember being very uncomfortable by it, but I turned around and went up the river and did not try to pay any attention to it at all," she said.
She also recalled that he always carried a backpack, which authorities described as his "murder kit." It contained a gun, duct tape and a knife.
"I remember seeing it in the truck. It was always with him, like a woman carries a purse," Lenna said. "Knowing that he had this kit inside of his backpack when he was around us every time is terrifying to me, and it's almost like a slap in the face to [know] how close it came for us. It was very, very close."
After Cary Stayner's arrest, Lenna said FBI agents contacted her mother.
"The FBI went in and spoke with my mom privately to let her know that Cary Stayner had confessed to initially wanting to kill my mom, and rape and kill my sister and I," Lenna said. "My mom was extremely shocked. That's when our lives were flipped upside-down. ... My mom went off the deep end, and um, harbors a lot of guilt. I don't blame my mom at all. Nobody could have known."
The family learned from the FBI that Cary Stayner had tried to kill them on three separate occasions including after he'd killed Armstrong. Before he'd driven to the nudist colony, Lenna said, Cary Stayner had gone looking for them but Lenna and her sister were at their grandmother's house.
Lenna told "20/20" she had kept this story hidden for 20 years, never sharing it with anyone. She said meeting with Rinek, the former FBI agent and author, had helped her discuss her feelings of survivor's guilt.
"Meeting with Jeff (Rinek) really brought it out that I can talk and I can have feelings about what happened," she said. "I want to speak out for my family, who's been affected. I want to speak out for other people who are surviving victims. And let everyone know that it's OK to still have feelings about it."
Lenna, whose daughter is now the age she was when she met Cary Stayner, said she had not returned to Cedar Lodge until last year. She said the visit "sent chills" up and down her spine.
"We're survivors... I loved him a lot -- I don't know if he knew how much I did. He was like a happy part of our life. And uh, such a happy part that turned into such a dark part of our life," she said. "There's a big part of me that still wonders if he still thinks of those two little girls that adored him so much because we think about him all the time, and I wonder if he still thinks about us."
Cary Stayner was convicted in both state and federal courts. He was sentenced to death in December 2002 and remains on death row.
Lenna said that after Cary Stayner's arrest, her family placed a Beanie Baby peace bear on a little, wicker float down the Merced River to give them peace about everything that happened.
"It's hard for me to think about him being behind bars, and I wonder what it's like for him being there, because he loved to be outside," Lenna said. "He loved Yosemite and in some way, it's sad. But I also don’t forgive him. I can't. But at the same time, I still have a hard time looking at him as a monster."