Rabbitohs star's biggest fan is on the frontline at Sutherland Hospital

However, while disappointed she can't be at the game, she is pleased she will be able to watch it on TV with her father, who is a huge NRL fan.

Ms Cook has worked as a nurse for 40 years - at St George Hospital, Prince of Wales Hospital and, for the last 12 years, at Sutherland Hospital where she is a member of the Aged Care Services Emergency Team.

She and her husband Graham were on a caravanning holiday in Queensland when the NRL relocated to the Sunshine State following the COVID outbreak in Sydney in June.

They were able to watch Damien play several games, but three weeks ago, with the COVID situation worsening, she returned to Sydney to resume her role on the frontline at Sutherland Hospital.

Her husband remained in Queensland and, with other family members, will be supporting Damien at the ground.

"I'm so proud of Damien and very happy his dad is there to cheer him on," Ms Cook said.

"I've never missed a game. Even when we are travelling, we watch Damien play as we have a satellite dish on our caravan."

Cook told AAP his mother had been on his mind the entire finals series.

He and his young family had little interaction with her last year during the the season-long NRL bubble, including the end-of-year State of Origin series.

After Friday night's preliminary final, they talked via FaceTime, but "it was pretty loud so I couldn't really hear what she was saying," Cook said.

Cook's grand final has been a long time coming.

He was part of Bulldogs squad for the 2014 grand final, but was overlooked for Moses Mbye when Michael Ennis was injured in the preliminary final.

Cook was born in Sutherland, grew up in Helensburgh and attended Endeavour Sports High School.

He played junior rugby league for the Helensburgh Tigers and was signed by the Panthers, Dragons and Bulldogs before joining the Rabbitohs in 2016.