By her own account, Becky Babcock had a healthy, normal life growing up in Bend, Oregon.
"My childhood was of dreams and we had every opportunity that we wanted. My parents wanted us to prosper, to learn and to grow," she said. "I had a great family, a great life. ... It was honestly picture perfect."
Becky Babcock, a 34-year-old behavioral health coordinator for children in Salem, Oregon, said although she feels like she's always known that she was adopted, at first, she didn't question where she came from.
"I was just like any other kid. And, we were just like any other family," she said.
The family was always on the go, windsurfing, fishing, hiking and skiing at Mount Bachelor. But, she said, at the age of 8, she started asking questions about the adoption.
Becky Babcock said that despite her supportive upbringing, she felt this need to know why her biological parents were not raising her.
"There was just a little part of me that felt like I was searching for something else," she said. "I was searching for that blood tie, in a sense."
When she was 11 years old, Becky Babcock tricked her longtime babysitter into revealing the name of her biological mother: Diane Downs.
Downs was a notorious killer in Oregon, convicted in the 1983 shooting of her three children that left one of them dead.
The revelation would shake Becky Babcock's young world and take her on a journey of self-discovery, filled with ups and downs, she said. After leaving the public eye in 2010, she spoke to ABC News' "20/20" to share her life now.
"The impact of Diane Downs being my mom has altered the course of my life so many times. But I'm on track and I'm really happy with the way life is," she said.
There was just a little part of me that felt like I was searching for something else.
Becky Babcock finds 'Small Sacrifices'
When Becky Babcock was young, her adoptive mother, Jackie Babcock, tried to appease her curiosity surrounding her adoption. She said her mother gave her "little bits of information" but the questions kept coming, she said.
Eventually Jackie Babcock decided the truth was likely too much for the youngster to handle, Becky Babcock said, and stopped answering her questions.
Becky Babcock said she'd previously learned from Jackie Babcock that a book had been written about her biological mother, so days after getting the name from the babysitter, she headed to a bookstore.
"At that point, I had a name and that was all I needed because I knew there was a book," she said.
At the bookstore, she found Ann Rule's book "Small Sacrifices," which detailed Downs' life and conviction, complete with pictures.
The book tells how on May 19, 1983, Downs had pulled her car up to a hospital's emergency door. Inside the vehicle, her children -- Cheryl, 7; Christie, 8; and Danny, 3 -- had all been shot multiple times at close range. Cheryl was dead.
Downs, who'd just moved to Springfield, Oregon, from Chandler, Arizona, told authorities that she and the children had been traveling down a road after leaving a friend's house at night when a man had flagged down her car.
The bushy-haired stranger, she said, wanted her car and pulled out a gun, shooting all three children. Downs, a 27-year-old divorced postal-service worker, also had been shot in her left arm before she was able to escape and drive away to a hospital.
But on Feb. 28, 1984, nine months after the shootings, Downs was arrested and charged with one count of murder and two counts of attempted murder. When she went on trial in May 1984, she was pregnant again. After a six-week trial, she was convicted.
Prior to her sentencing to life plus 50 years, Downs gave birth to a baby girl whom she named Amy Elizabeth. The baby was taken by the state and delivered to adoptive parents. That girl was later renamed Rebecca "Becky" Babcock.
"I saw who she was and what she looked like," Becky Babcock said about looking at the pictures in the book. "It wasn't a face that I wanted to see. ... Just the cold look in her eyes scared me. ... The reality set in that that's who gave birth to me. ... I slammed the book shut and I left."
She said she didn't tell her parents what she'd learned about her biological mother.
Over the years she learned more details about Downs. It wasn't until she was 16, however, that she saw the two-part miniseries based on the book at a boyfriend's house. She said she'd shared with him some details about her biological mother and unbeknownst to her, he'd rented the tape.
Becky Babcock said watching the film "broke" her heart and her life went into a "downward spiral."
"It was gut-wrenching. It changed me. ... My innocence was gone," she said.
Reaching out to Diane Downs
Becky Babcock, who said she'd already started becoming more rebellious in school and at home before watching the movie, began taking "more intense" drugs and dating a number of people. She moved out of her parents' home in Bend and dropped out of school.
"I was living with my boyfriend or living with friends," she said. "I was not nice to my parents. I was angry. I was hurt. ... I lashed out."
Becky Babcock said there were some aspects of Downs' character that she related to: the need for attention, love and belonging.
"It was very scary to have any relation to that woman. ... That's what really scared me. ... To feel any sort of connection to such a monster. ... A part of me was afraid that that's where I came from, does that mean where I'm going?" she said.
At the age of 17, Becky Babcock learned that she was pregnant with her son, Chris.
"I love my son with everything that I am. ... But being that young, I didn't understand what being a mom was. I didn't realize that life had to do a 180. ... I continued doing the things that I shouldn't have been doing. ... I was still out being a teenager," she said.
Eventually, she left Bend for a job in Klamath Falls. She was 21 and had gotten engaged, got a good job and then in 2006, she had her second son. But, before she gave birth, she and the baby's father broke up and she was forced to move into a homeless shelter. She called her parents and placed the baby for adoption.
After her second child had been adopted, Becky Babcock said, she felt drawn to finally reach out to Downs.
"I wanted her to be a person. I wanted to relate to her not as a mother, because I had a mother, just as somebody that was heartbroken to give up their child," she said. "I was hoping to have a connection."
Becky Babcock said the first exchange of letters between her and Downs was positive.
As more letters continued to arrive, however, the content grew stranger, she said.
"They progressively got more and more insane -- conspiracy theories, people watching me my whole life -- just really scary things. And that's when I completely regretted messaging. ... She sent, you know, 12 pages of how she's innocent, and, 'This is who really did it,' she thinks," Becky Babcock said.
She said Downs even accused her of being a part of a conspiracy against her and trying to harm her. Becky Babcock eventually asked Downs to stop contacting her.
"I had to accept that she really does struggle mentally," she said. "She really does have something wrong with her. And, it doesn't mean that I do too."
When I was young, I worried that I would be like Diane Downs. As I grew up, I realized nature is not gonna win over nurture.
Becky Babcock takes her story public
In 2010, she did a media blitz, interviewing with Glamour magazine and then ABC News' "20/20" and Oprah Winfrey's talk show. Then, Becky Babcock decided she would step out of the spotlight.
"I felt like I had, you know, put myself out there, told my story like I had wanted to, and it was time to move on," she said.
Afterward, Becky Babcock said she suffered some health issues but took up yoga and meditation and began feeling healthier. She also changed her degree program and found a passion in psychology.
She said she'd also reached out to her siblings Christie and Danny, who were both adopted by the prosecutor who tried Downs. She said both had told her they were not interested in talking and wanted to live their lives "without the stigma of being Diane Downs' children."
Becky Babcock said Rule, whom she eventually met before the author passed away in 2015, had given her some details about her father but not his true identity.
"I was searching for the other half of who I am and where I came from. I have the side of Diane Downs. And I was hoping to find the opposite," she said. "I know I came from a monster. I was hoping that the other part of that wasn't, that it was the opposite, that it was somebody full of love and kindness and generosity."
Becky Babcock recently bought a new house and is feeling upbeat about her life and her role as a mother to Chris. She said she was speaking to ABC News' "20/20" again to share with others how her life had changed since 2010.
"When I was young, I worried that I would be like Diane Downs. As I grew up, I realized nature is not gonna win over nurture," she said.
Becky Babcock said that she'd spoken to her son, Chris, now a 16-year-old high school sophomore, about Downs. She said that she'd told him when he was about 8 years old and that he'd received the news "well" and had asked questions, as she did years ago.
"I look at him and I am just so impressed. ... I compare where I was at that age to where he is and my heart overflows with joy and pride," she said.
She said that she was incredibly proud of her son, who practices jiujitsu, and that the two enjoy spending time together, walking the dog or just watching a movie at home.
Chris told "20/20" he didn't have a desire to connect with Downs.
"I already have a pretty amazing grandma. ... I don't need someone like that in my life. ... The hole's already been filled and the spot's already been taken," he said.
As for Becky Babcock, she said that she has no more questions for Downs and that she no longer wants to see or hear from her.
"It's taken me a long while to get to the place where my story is my own. ... I've worked really hard through life to overcome those obstacles. To realize that even though that's biologically my makeup, it's not who I am inside. ... I have closure to the whole situation," she said.