Linda O’Keefe was just 11 years old when she was sexually assaulted and murdered in Newport Beach, Southern California, in 1973.

More than four decades later, James Alan Neal was arrested and charged earlier this year over the killing after he was identified as a suspect through genealogical DNA.

Here, Linda’s sister Cindy Borgeson tells Sky News how she hopes the crime-fighting tool will help finally solve the cold case and bring her family justice.

I was having a cheeseburger when I got the call from the detective.

He said: “Are you sitting down?”

I said yes.

He said: “Well, I want to let you know I just arrested the man who murdered your sister.”

It was surreal. It is 46 years since my sister Linda went missing. They found her body the very next day.

Some people from the university were going down a path below the bluffs and they saw the high grasses were crumpled and that’s where they found her.

She was 11 but she was like an old soul. She loved old blues records, she just had this real peace about her. She was just very sweet, she’d go with the flow.

As a parent and a grandparent myself now I cannot imagine how devastating it was for my parents.

When I see stories in the news now, I feel that heartache.

Yes, I lost a sister and that’s a terrible thing, but as a parent I can’t comprehend how that how awful it would be.

There was a story that a woman saw my sister talking to a man in a van on her way home.

After that everywhere we went, if we saw a turquoise van, my father would chase it, convinced that he was the guy.

The reason it went unsolved for so long was that they did not have this new genealogy technology that Parabon NanoLabs have come up with. Without it, it may never have been solved.

He [Neal] was identified by familial DNA. Someone he was related to, and DNA the police had kept from the murder scene, were a match.

They can track people to six degrees of separation, from a fifth cousin. That is fascinating to me.

They are solving cases all over the country. I think it is wonderful if it helps them track down people they have never been able to track down before.

The detectives have had several calls from other people who lost loved ones around the same decade.

They said they can’t guarantee the same results, but are going to use the same tools to hopefully solve their cases as well.

I have a really strong faith that sustains me through everything I’ve gone through.

When we found out that this man had a wife and children and grandchildren, we realised what a shock it must have been for them.

I have friends who say I should be angry and want to string him up, but he has a family that has been disrupted as much as mine was destroyed. The grief is the same.

I forgive because unforgiveness is like taking poison and wanting the other person to die.

It doesn’t do me any good to hold on to that. As my husband says, it’s like expecting the person that put a knife in your back to take it out for you.

I had closure when they found her body. So many families never get that. This is an additional level of closure.

I believe that justice will be served in this case. What that looks like is not up to me. It is up to the court.

Neal has pleaded not guilty to the charges against him.