Born Peggy McBride in Belfast, she came from a large working-class family. At Gallaher's cigarette factory, she became a shop steward and eventually joined the Communist Party of Ireland, where she met Eddie Darley, a shipyard worker. They married in 1955 in England, while working as hop-pickers.
Both were active Communists in Northern Ireland in the late 1950s and during the 1960s, being especially involved in the civil rights movement. As sectarianism increased, they decided to emigrate, but were denied entry to Australia, probably because of Eddie's membership of the Communist Party there in the early 1950s.
Instead, in 1971, they left for New Zealand, where three of Peggy's siblings already lived. Eddie worked in the power stations and eventually they became permanent residents. This gave them another path to enter Australia, in 1978. Eddie got work at the Moombagasfields, in South Australia, and the family settled in Adelaide.
Peggy and her family quickly got involved in the community. She supported resident associations, environmental groups and cultural events, and in the 1990s campaigned for the left-Labour, Green and Democrat "progressive caucus" on the Port AdelaideEnfield city council. She died in Adelaide in 2010, aged 83