On this day Tyler should have been celebrating his 15th birthday, but instead his family will be honouring his life after he was killed in a car accident on July 11 near Mendooran.

The crash left Tyler and a 25-year-old man dead and three people injured.

Tyler's brother Nicholas, 13, sister Shanisha, 17, and their mother Kerry Sunderland were all airlifted to hospital following the accident.

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Speaking to the Mudgee Guardian in the days after the crash, Tyler's older brother Callum said his family had been left heartbroken.

"We're just in a lot of shock, it hasn't really hit us yet," he said.

"I don't think it'll hit us until we bury him."

On Friday Shanisha spoke for the first time since she was airlifted to Newcastle's John Hunter Hospital with leg fractures.

"My sister's started talking again this morning, she hasn't said anything since the accident," Callum said.

"She was unconscious for a while so this is amazing."

Nicholas, who is at the Children's Hospital at Westmead with multiple leg fractures, is also "awake".

"This is really good because they had to sedate him for a while the other day," Callum said.

"He took it really hard when he found out about Tyler because they're really close in age."

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Mrs Sunderland has been in Westmead Hospital with arm fractures but was expected to be released on Friday.

"Mum is in a bit of shock," Callum said.

In the aftermath of the crash that took his young brother and his mother's partner, Callum said each day has been a struggle.

"Yesterday was really hard, but then I know my brother wouldn't want me to keep sitting there crying for him," he said.

"It's better to keep on moving than to curl up in a ball and cry."

On Saturday, Callum and some of this extended family will release purple balloons in honour of Tyler from their property in Menah just north of Mudgee. Tyler's favourite colour was purple.

The Sunderland family are originally from Dubbo and before that Coolah, but moved to Mudgee four years ago.

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"Everyone's been really amazing and doing everything they can to support us and sending us lovely messages of support," Callum said.

A family friend of the Sunderlands, Amy Williamson, has set up a GoFundMe page to help raise funds to cover the cost of Tyler's funeral and the family's medical bills.

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