Shirley Doreen Venn, a publicty manager, married Greg Shackleton (q.v.) at St Peter's Church of England, Glenelg, Adelaide, on 7 May 1966.
After a period working in America they returned to Melbourne in 1968, where Greg Shackleton was a general reporter and news presenter with television-station HSV-7. On 10 October 1975 Shackleton was sent to Portuguese Timor to report on the conflict between the Revolutionary Front of Independent East Timor (Fretilin) and factions supported by Indonesia. He and four other journalists and camera men died on the 16 October as a result of an assault by Indonesian soldiers against a Fretilin force at Balibo. These men have since become known as the Balibo Five, whose story has been told in several non-fiction books including one by Shackleton herself, and in a motion-picture.
His widow, Shirley Shackleton, campaigned unrelentingly for over thirty years to reach the truth about this incident. A coronial inquiry into the death of one of the journalists, Brian Peters, a British national, was finally held in 2007 in Sydney, New South Wales.