The builder and sometime model - who got engaged to former Miss Universe Australia Hawkins in December 2010 after seven years together - joined his two brothers as pallbearers at Lesslee's funeral on Monday (February 13).
According to The Daily Telegraph, Hawkins cancelled various business commitments and flew to Newcastle to be there with her fiancé following his mum's death.
Leslee apparently passed away while waiting for a liver transplant. She had undergone another liver transplant last year, but her body rejected the organ.
Leslee and Hawkins' mother Gail threw Wall and Hawkins a lavish engagement party at Sydney's Palm Beach last March and the couple are believed to be planning their wedding for this year.
Hawkins recently said of her wedding plans: "I'm so excited, I can't believe it's all happening. Nothing's completely locked in yet but we've penciled a lot of stuff in. It's all coming together."
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