Mom of Daughter Thrown Off Cliff: 'You Just Learn to Live With Your Pain'

Justice has come at last for a little girl thrown off a cliff by her own father.

A jury found Cameron Brown guilty of murder in the first degree for taking his four-year-old daughter, Lauren, to a remote cliff in California and flinging her over the edge.

Read: Dad on Trial for Third Time for Murder After Allegedly Throwing Toddler Off a Cliff

Brown was defiant to the end when he heard the verdict. "Judge, I'm innocent, I have no comment," he said.

Lauren's mom, Sarah Key-Marer, clutched Kleenex as she left the court. "All I ever wanted was that he would take responsibility for what happened that day," she said. 

In an exclusive interview with INSIDE EDITION, Lauren's mom says she waited 15 heartbreaking years to hear the word, “guilty.”

"There's never closure. You just learn to live with your pain," said Key-Marer.

Prosecutors said Brown killed Lauren to avoid paying child support - and to spite his ex.

This was the third time Brown stood trial for throwing Lauren off the cliff. Two previous juries were deadlocked, first in 2006 and then in 2009.

Deputy District Attorney Craig Hum, the prosecutor in all three trials, said, “One of the toughest things in this case was to convince 12 people that a father would actually do this to their daughter. It's really hard to believe and in the first two juries, some of the jurors had a hard time believing someone would do that.”

Lead Detective Jeffrey Leslie has also been on the case for 15 years. “I was very, very hopeful that justice would be served, and I was confident that we could get there,” he said.

Read: Man Who Fatally Shot Neighbor Says He Acted In Self-Defense

This time, the jurors' guilty verdict was unanimous - and resounding. “Ladies and gentlemen of the jury, is this your verdict, so say you one, so say you all?” asked a court official.

The jury replied, “Yes.”

After the verdict, juror Sheila Jones said, "I'm sorry to Sarah for all the pain she has been going through. I'm sorry for the death of your baby. But justice has finally been served!"

Just last week, as Brown stood watching, the jurors were taken to the cliff where Lauren met her death.

"It's been a long time, just reliving the tragic circumstances, and now we can move forward and remember the happy times that we remember with her," said Key-Marer.

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