Fifth-generation direct descendant of the Cavanoughs, Pat Holdorf, 83, told The Gazette the pair arrived in 1788; Owen as a sailor on the Sirius and Margaret as a convict on the Prince of Wales.

Under the name ‘Margaret Darnell’, she had been sentenced to transportation for stealing six knives and forks to the value of six shillings in London.

They were sent to Norfolk Island from the Sydney colony as part of a population program and were married there in 1791.

Mrs Holdorf, who unveiled the little commemorative plaques, said the couple returned to Australia in 1796 and Owen was given a land grant at Ebenezer. He later donated the land for Ebenezer Church.

Mrs Holdorf said the Fellowship of First Fleeters had contacted her when they wanted to put its group’s plaques on the historic couple’s grave.

The original headstone was moved to Ebenezer Church’s cemetery in 1966, but a replacement headstone to mark their grave-site was not made until 1988. It was fashioned from sandstone quarried on the Cavanough’s land, and a large brass plaque was affixed.

The ceremony was conducted by Reverend Grant Bilby of Ebenezer Uniting Church and Bruce Arnett of the Fellowship of First Fleeters. Reverend Bilby said the couple had a special place in our history, “and contributed a lot to early European settlement of this land and country, and so we should, as a nation and people, remember them”.