Hi Mary,
Have found a Mary Harris - parents John and Mary 4397/1959. No district stated. The only Mary Harris born between 1855 and 1870 with parents John and Mary.
Lots of Mary Harris or Mary A Harris or Mary Ann Harris in marriage records between 1875 and 1925. No hope of knowing without reading each certificate for parents info.
Have found reference to Philip and Catherine Mackel who had 7 children registered in districts Sydney, Berrima and Wollongong from 1858 to 1871.
In 1870 Phillip Mackel was appointed Master of the Post and Telegraph Office in Wollongong. Also an historical story in the Illawarra Mercury by Michelle Hoctor, Oct. 12, 2012 about Phillip Mackel petitioning the government for a fishing vessel for local Aborigines.
A marriage notice in Sydney Morning Herald 9 Oct 1879 for Katie Agnes, daughter of Phillip and Catherine Mackel, Wollongong and ? Cheadle of Coventry, England.
BDM records show Kate A Mackel marriage to William A Cheadle in district of Wollongong. Ref: 5259/1879.
Phillip and Catherine Mackel had a daughter Catherine born 1858, district Sydney. Ref: 600/1858.
Another reference to the death of a daughter Florence Adeline, aged 8 years on Sept 10 1877, at the post office.
Scallywag