Trotter was born on the North Shore, Auckland. Her parents had emigrated to New Zealand from Ireland in 1920. She attended Hastings High School and Woodford House.[1]
Trotter and her husband formed what became a part of the Fletcher Challenge Art Collection, which is now one of the largest curated private collections of New Zealand art.[3] Trotter was a founding trustee and life member of the Wellington Sculpture Trust, an organisation which was established in 1983 to support innovative public art in the city.[3]
Trotter's other community roles included positions with United World College, the Salvation Army Advisory Board, the Board of Wanganui Collegiate School and Wellington Sea Rescue Service.[1]
Trotter was married to businessman Ron Trotter until his death in 2010.[4]