Mrs Cobb (91) has been involved with the association since 1960, when she became leader of her daughter Helen Doney’s unit.
She later travelled around WA to train other Girl Guides leaders and has held senior positions in the group.
Mrs Doney said her mother enjoyed being part of the association.
“She loves the camaraderie and service to others,” she said.
“She’s also a huge fan of camping and really enjoyed getting out and teaching the girls camping skills like pitching a tent.”
Mrs Cobb is a life member of the Trefoil Guild in Burswood, which celebrated with a morning tea last month.