From ABC News headquarters in New York City, this is GMA3.

We do begin with the main paddle border murder.

A 17-year-old has been charged as the owner of the campground where it happened is speaking exclusively to ABC News.

Our chief investigative correspondent, Aaron Kuturski, has all the details. Aaron?

And well, the owner of the campground knows all of her summer renters and at first thought

Sunny Stewart's killer had to be a stranger, not somebody living among them under her nose,

and certainly not the teen.

She described as awkward and dorky who's now charged with murder.

The owner of the campground wears Sunshine, Sonny Stewart, and the 17-year-old now charged with murder. The owner of the campground where Sunshine Sunny Stewart and the 17-year-old now charged with

killing her both stayed is speaking out.

Never ever did I ever expect anything remotely like this to happen here.

It's absolutely shocking.

Catherine Lunt, the owner of Mick Mackack Campground, met Stewart in April.

Sunny was very excited to be on the lake and paddleboard.

Early evening July 2nd, Stewart took a swim, then hopped on her paddleboard to explore

splendid Crawford pond. She never returned. Police found her strangled and bludgeoned to death

on 100-acre island. While rescue teams searched the water for answers, Lund reviewed her surveillance cameras for

any sign of the killer.

I know every vehicle that comes in this campground.

I decided that it was best for me to review the footage because I was looking for a stranger.

Two weeks later, authorities identified the suspect as 17-year-old Devin Young. Young was taken for a stranger. Two weeks later, authorities identified the suspect

as 17-year-old Devin Young.

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