Allison Moorer and her sister, Shelby Lynne, are both acclaimed singer-songwriters – Allison with an Oscar nomination, and Shelby a Grammy Award. But they also share a childhood marked by one devastating moment, when their father shot their mother and then turned the gun on himself.

In her stunning new memoir, "Blood" (Da Capo Press), Moorer writes about the legacy of that murder-suicide: two sisters' lifelong quest to make peace with their past, and the power of human resilience.

Da Capo Press

For most of Moorer's life, the story of her parents has been hiding in her music: "Every record I've ever made has got some song on it that has something to do with this, something to do with my parents," she told "CBS This Morning" co-host Anthony Mason in her first and only TV interview.

Over the past few years, the 47-year-old singer has been researching her mother and father, especially their deaths. She even sent away for autopsy reports.

"I wanna know why," she said, "so that I can come to terms and say, 'Okay, well, what I'm really trying to do is forgive.'"

"Can you do that?" Mason asked.

"Yeah. I needed to do it so that I could be happy."

In her new memoir, "Blood," Moorer tries to find proof that, as she writes, "we weren't and aren't ruined by it all."

"I'm still trying not to be the daughter of a murderer. I'm still trying not to be the daughter of an abused and murdered woman. I'm still trying to redeem them," she writes.

Franklin and Lynn Moorer raised their daughters in Frankville, Alabama. Allison and her older sister, Shelby, grew up surrounded by music. In a recording of the family singing and playing together in the mid-1970s, Allison sang high harmony, her mother low harmony.

Their father was a teacher and an aspiring songwriter. But Franklin Moorer also had a drinking problem and a mean streak.

Mason asked, "You used to say a prayer every night. What was that prayer?"

"'Please, God, don't let daddy hurt mama,'" Moorer said. "And I would say it over and over and over."

What was it that she felt in the house? "Terror."

One day, while playing with Shelby, Allison fell off the family horse. "Our daddy hit my sister in the face for it," Moorer said. "When your daddy beats the crap out of you, how are you supposed to feel like you're worth anything?"

In her stunning new book and album, singer-songwriter Allison Moorer reflects on a lifelong quest to make peace with her past, and the power of human resilience. CBS News

In 1986, Lynn finally left her husband and moved with the two girls to a rental house. In the early hours of August 12th, Franklin paid a visit. Allison was awakened by the shots. Shelby went outside, and on the front lawn, she found their father had shot their mother and then turned the gun on himself.

"I think he just broke," Moorer said.

Shelby, at 17, and Allison, 14, were suddenly orphans. "It's a difficult thing to walk through the world and not belong to anyone," Moorer said. "So, we belong to each other, and we have always felt like that."

Moorer has never been back to that house, but it has never stopped haunting her.

"The tragedy colors everything," she said, "and all the good feels a bit bittersweet."

Mementos of her parents are all over Moorer's Nashville home. "My mama was a great mama," she said. "And she is why I'm okay. She is why my sister is okay."

"What did she give you?" Mason asked,

"She never ever let me believe that I was not loved."

If she has often doubted her father's affections, she still held onto his hat; it travels with her. She also has his briefcase and his guitar.

Mason asked, "How do you feel about him now?"

Singer-songwriter Allison Moorer. CBS News

Emotional, Moorer replied, "I feel nothing but love."

"How did you get to that?"

"Time," she said. "Time. Investigation. Willingness, and having a little boy."

How did that make a difference? "I got to see and experience a little boy and know that my daddy was one at one time."

Her son, John Henry, is autistic. She knows one day she'll have to explain the family history.

Mason asked, "Did you figure out what you're gonna tell John Henry?"

"Probably that his grandparents were troubled and beautiful, like we all are," she replied.

You can stream Allison Moore's album "Blood" by clicking on the embed below (Free Spotify registration required to hear the tracks in full):