Selina and her friend Maree Alchin, who nominated her, said being in Sydney in the lead-up to Thursday's announcement had been truly memorable as they bonded with the other women.

"It's been overwhelming and amazing," Selina said.

"No one is upset that someone else won it. When you get to know them, they're just beautiful people."

Maree nominated Selina for fostering three children and contributing to the community of St Anthony's Primary School and across different causes in Canberra.

"It wouldn't have mattered who won, because they are all deserving and all beautiful, lovely people," Maree said.

Tasmanian mother Carol Edmunds, 53, who took out the national title, was nominated by her stepdaughter Kelly Haywood, 38.

Thirty years ago, as a young wife, Mrs Edmunds made the life-changing decision to take in her husband's eight-year-old sister, Kelly, who had just lost her mother to suicide, and to raise her as her own.

Carol treated her young sister-in-law as her daughter, taking care of Kelly's every need and filling in for her late mother throughout her teens, 20s and 30s.

"Growing up, I never wanted for anything; they fed me, clothed me, took care of my schooling and, most importantly, loved and cared for me," Kelly said.

"Carol believed in me at times when I didn't believe in myself and she encouraged me to be whoever and whatever I wanted to be."