Family of seven-year-old quad bike victim forced to break the tragic news to his twin.

The family of a seven-year-old boy killed in a quad bike accident in NSW’s Riverina region have remembered him as a “special, soft boy” who shared a close bond with his twin brother.

Connor Irvin died in Canberra Hospital on Monday, after a crash on his family’s property in Barellan, 60km east of Griffith the previous evening.

The boy’s aunt, Kelly, told The Daily Advertiser that Connor’s family yesterday completed the harrowing task of sharing devastating news with his twin Bailey, who she described as his “best friend”.

In a heart-breaking Facebook post, Connor’s older sister, Shenaye, promised him she’d watch over their grieving brother.

“Fly high my big blue eyed angel,” she wrote.

“We are staying so strong for you. Promise I’ll look after your best mate until you’re together again. I’ll be seeing your gorgeous smile again soon baby.”

An Irvin family friend earlier issued a statement on their behalf.

"Connor comes from a very loving family; he was a very special, soft boy who loved his twin brother Bailey and his sister Shenaye," it read, according to The Daily Advertiser. "He loved his dad’s farm.”

The bike, a low-powered 110cc children's version, had been given to Connor as a Christmas present.

A nine-year-old boy was also on board when the vehicle tipped over, but managed to jump clear and avoid being crushed. Both were wearing helmets at the time.

Griffith police Inspector John Wadsworth said Connor's family, including his parents Mel and Dennis, were present when the accident occurred.

“It was an extremely traumatic scene with family members trying to help the young fella and everyone doing their best to save his life," Inspector Wadsworth said.

“They are obviously extremely distraught by this tragedy.”

Connor is the second person to have been killed in a quad bike accident in Australia so far this year, following ten deaths last year and 21 in 2015.