Prosecutor Rob Wood said in court Monday, "What is the value of a human life? What is the value of a 16-year-old girl? … A 7-year-old boy with special needs? What is the value of a life of a mother and a grandmother?"

"We are calculating and assigning a value for the lives of Tylee Ryan, J.J. Vallow and Tammy Daybell," he said, noting that Lori Vallow Daybell "assigned a value of zero."

"This defendant violated the most sacred trust that exists in society -- that between a mother and her children. And she did it for gain -- she did it for money," he said. "A defendant who is willing to murder her own children is willing to murder anyone. Society can only be protected from this defendant by a life sentence without the possibility of parole. ... There's no rehabilitation possible."

Wood said Vallow Daybell can only be rehabilitated by "facing the consequences" of her crimes, which he said should be a life sentence without parole.

"The impact of the murder of Tylee was horrendous," Wood said.

The body of Vallow Daybell's 16-year-old daughter, Tylee, "was utterly destroyed, and she was buried in a pet cemetery next to animals," Wood said.

Seven-year-old J.J., Wood said, likely endured "fear and betrayal" in his last moments alive, and was then "buried like a piece of trash."

A statement was read in court on behalf of Vallow Daybell's only surviving child, Colby Ryan.

"Tylee and J.J. brought so much light into this world," Ryan said. "My girls will never have a chance to know them."

"I want them to be remembered for who they were," he said.

"Tylee was sweet and kind, funny and bold," Ryan said, while J.J. was "the most fun, sweet and silly kid I've ever known."

"I pray for healing for everyone involved, including those who took the lives of all the ones we loved," he said.

J.J. Vallow’s grandmother, Kay Woodcock, spoke in court Monday about what she called Lori Vallow Daybell's "cruel campaign of terror."

"J.J. and Tylee could have been with us living happy lives," she said as she started to cry.

"Instead she took all that away," she said, calling Vallow Daybell a "monster."

"Today I take the power back by standing here, speaking out loud about all the pain and loss she's caused," Woodcock said.

Woodcock recalled the birth of J.J., who was born premature and with illicit substances in his system. "As soon as I laid my eyes on him I knew he was my grandson," she said.

"He was a champion and oh so very special," she said through tears.

Lori Vallow Daybell and her then-husband, Charles Vallow, later adopted J.J.

Woodcock and her husband would still often visit, and she noted that her "incredibly smart," compassionate and empathetic grandson "had an innate and unbroken attachment to us."

Woodcock, choked up, said, "That same mother murdered that same child she expressed deep appreciation for. It is mind-boggling."

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Kay Woodcock reflects on grandson JJ Vallow's life during her impact statement

J.J.'s grandmother asked why Lori Vallow Daybell chose to adopt J.J., only to kill him a few years later.

"What did Lori deprive the world of?" she said.

"I will only have the precious memories to cling to," she said through tears.

Lori Vallow Daybell's daughter, Tylee, was 9 when J.J. became her little brother. "She doted on him and J.J. loved every minute of attention," Woodcock said.

Vallow Daybell was found guilty of the first-degree murders of J.J., 7, and Tylee, 16, who were killed in 2019.

J.J.'s "life was expendable to [Vallow Daybell]," Woodcock said. "His materialistic, self-centered mother cruelly and brutally stole his life -- and him from the world. Lori's acts of depravity, cruelty and betrayal have no limits."

When J.J. and Tylee were missing, "fears continued to mount daily," Woodcock said.

When she learned J.J. and Tylee had been "buried like animals" in Chad Daybell's backyard, Woodcock said she let out a "guttural" sound.

"We were destroyed," she said.

Woodcock called Vallow Daybell "a danger to society."

"She is driven by her greed and her need to be the center of attention," she said.

She said she believes Vallow Daybell should be sentenced to life in prison.

Vicki Hoban, the aunt of Chad Daybell's wife Tammy Daybell, who died of asphyxiation in 2019 less than one month before Chad and Lori Daybell married, gave a victim impact statement through tears on Monday.

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Vicki Hoban gives impact statement at Lori Vallow Daybell's sentencing

Tammy Daybell's aunt gave her statement through sobs as she spoke of her niece.

"Tammy was a most excellent person and she led her life with the utmost dignity," Hoban said. "There will be a huge void."

Her niece was "brutally executed in her own bed," Hoban said as she wept, "taken from us by murdering thieves."

Tammy Daybell was "robbed of her entire life," she said, and "all her family robbed of ever seeing her again."

"Heartbreaking, gut-wrenching, unbearable is not a big enough statement," she said. "The most innocent of lives was simply discarded like it meant nothing."

Hoban said Vallow Daybell turned her niece's "home into a cemetery," adding, "Tammy would have been horrified to know what you have done -- and it's broken us as a family."

Chad Daybell is charged with Tammy Daybell's murder and conspiracy to commit murder and pleaded not guilty. Vallow Daybell was found guilty of conspiracy to commit Tammy Daybell's murder.