"I saw him that morning," she said. "It was just another day. He had to go help with the sheep, he didn't want to do it and I said 'Look mate, everyone has to work on their birthdays, get used to it'."

That would be the last interaction Ms Worldon ever had with her only child and early the next morning she was told the devastating news.

"It was 4.30am and (Braydon's stepdad) Peter got up because there was a car here and he called out to me," she said.

"I'm a heavy sleeper and I woke up and had this feeling from the top of my head to the tip of my toes and I knew something wasn't right. The police told us and my heart broke."

Ms Worldon said she couldn't understand how someone could leave her son lying on the road and months later, the police are still searching for answers.

"Who would do that?" she said.

"I was numb, angry. You can't cope. I don't know if anyone could ever cope. The only thing they could tell me, which was a relief, was that it was instant and I spent hours that morning, before I was told, wondering."

As a baby, Ms Worldon said she loved Braydon the minute he was born.

"As a baby, you just never wanted to stop cuddling him," he said. "You never wanted to put him down, everyone wanted to hug him and would fight to hold him."

The family lived in Wagga until Braydon was about three and then moved to Wantabadgery.

"He loved all the space that he had out there for adventures," Ms Worldon said.

"There is so much that we did together, he used to drive me nuts when the show came to town. The Wagga show, the Junee show - it didn't matter he wanted to go to them all."

Ms Worldon said the dodge-em cars were his favourite and she would spend hours waiting for him while he would take numerous turns.

"He would deliberately bump into everyone and he was so funny to watch, the way he would go around and would go directly for someone," she said.

"After being in there with him once, that was enough for me because then he would aim for me every time."

Ms Worldon said Braydon was a cheeky rascal, but was lovable and kind and not afraid to stand up for what was right or who needed it most.

"He helped a lot of kids out that he went to school with at Wagga High," she said. 

"There was one girl, she has cerebral palsy and she was getting picked on and he would stand up for her. We always taught him that it didn't matter what someone has got, you treat them like anyone else and he would always follow that."

Braydon loved to fix and invent items for the property.

"He's always been a worker, ever since he was little," Ms Worldon said.

"One time, he made a hitching rail except it was for tools and he was just bored one morning so decided to put it together to hang the tools on it.

"He never really was the sort of person who boasted. If there was a hole or a problem he would fix it up and never say anything."

Ms Worldon said the last few months have been extremely difficult.

"I miss him all the time," she said.

"As a parent, you never expect to be here after them, you are not supposed to be. They're supposed to be outliving you. It's not fair. It's still so hard to believe, I keep hoping that he will just come around the corner."

Ms Worldon said not knowing who was responsible is the worst part.

"The only thing that would help us was if he was still here, but nothing can bring him back," she said. "Someone has to know something, don't say you don't. We just want whoever did it to come forward."

Ms Worldon said she wishes she could tell Braydon how much she loved him.

"I'll remember Braydon for everything, his personality and his cheekiness, I really miss that," she said. "I wish I could tell him I loved him."

Ms Worldon pleaded for anyone with information to come forward to the police. 

Officers from Riverina Police District have been appealing for public assistance since December to help piece together how Braydon Worldon died.

Strike Force Dunstable was established by the Crash Investigation Unit, with assistance from Riverina Police District, to investigate the circumstances leading up to the death of the 15-year-old.

About 1.30am on December 19, 2018, emergency services were called to River Road, Wantabadgery, about 40 kilometres east of Wagga, after a passing motorist saw a body on the road.

The driver stopped to render assistance and discovered it was the body of Braydon.

As inquiries continue, investigators are appealing for information from the community or anyone with dash cam vision to come forward.

The boy was last seen alive during the evening of December 18, 2018, and police believe he may have been hit by a vehicle travelling on River Road.

Wagga Police's Inspector Andrew Spliet said police are still investigating the matter and calls on anyone with information to come forward.

"The information can be given confidentially," he said.

Anyone with more information is urged to contact Wagga Police Station on 6922 2599 or Crime Stoppers on 1800 333 000.

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