NRL great Brett Kimmorley breaks down on live TV as he talks about his wife's death.

Just weeks after losing his wife Sharnie Kimmorley to brain cancer, the rugby league legend has broken down on live television while speaking about her death.

Sharnie passed away in March at age 38, just eight months after she was diagnosed, leaving Brett the sole parent to four daughters: Maddi, Mia, Ava and Ivy.

Appearing on Fox Sports show League Life, Kimmorley spoke about this week's NRL round being dedicated to raising money and awareness about the disease, with proceeds going to 'Beanies for Brain Cancer'.

Choking back tears, Kimmorley spoke about his daughters' efforts to do whatever they can to raise money for charities that help support others going through the same thing as their family.

"My children have done their own things to help mum," he said.

"They did Relay For Life last week, as something special they wanted to do for mum...Everything we do at the moment is an us decision, not so much a me or an I decision."

"[We are] trying to take something that Sharnie tried to say to us last year, that she could handle it," he continued.

Breaking down, Kimmorley added that the family were "trying to carry on" her legacy.

The sportsman - who was married to Sharnie in 2000 - also added that it's been "very isolating" since she passed away in March.

"You feel lost and empty and all that...you certainly need people to ask you questions," he said.

"You rely upon your close friends and the people that are around you."

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