But his young life was snatched away in a tragic school bus accident on the afternoon of September 10 last year.

Yesterday his parents Sarah and Dean Dunn ensured his legacy and sense of fun was passed on to Harry’s playmates and fellow students at St Catherine’s Catholic College in Singleton.

The family, which also includes Harry’s younger siblings Luke, 8, and Georgia, 5, opened a new playground at the school featuring a six-metre-high climbing pyramid known as ‘‘Harry’s Climb’’.

‘‘Harry loved to climb about. He could climb like a monkey,’’ Mrs Dunn said.

‘‘This is a place where people can smile, say his name and laugh. It’s not a sad place. It’s a place for fun. It’s also a place to sit and reflect on memories of Harry.’’

More than 1000 people including kindergarten to year 12 students and members of the Singleton community gathered at the site on Friday to release green balloons for Harry.

Many were clearly emotional as they released the balloons in Harry’s favourite colour and played his favourite music.

Luke, who was injured in the school bus crash and airlifted to John Hunter Hospital, sang his brother’s favourite song, Fireflies by band Owl City.

Construction on Harry’s Climb began on what would have been Harry’s 10th birthday on February 6 this year.

‘‘Dean and I poured our heart and soul into it,’’ Mrs Dunn said.

‘‘As such it has become a sacred place for us. It doesn’t lessen our enormous grief but it has helped us survive.’’

The couple also thanked the school and local community for their support since their son’s death.

A truck driver will plead guilty next week to causing the crash  that claimed Harry’s life, the driver’s solicitor has told Newcastle Local Court.

Daniel Ronald Hennessy, 34, of Queensland was charged with dangerous driving occasioning death after the truck he was driving collided with a school bus at the intersection of Kelso and Church streets, Singleton, in September last year.

In July this year, Transport Minister Gladys Berejiklian announced the state government would spend $208million over the next decade installing seatbelts on buses operating on school runs in rural and regional areas.

The rollout covers buses in Singleton, Muswellbrook and Dungog.