Lauchlin was my paternal g-grandfather. He was born 1845 +/- 1 yr. Gabarus is one suggested POB, but one of his children, at least, was born in Port Morien, so that's also a possibility. His wife was Sophia Elsie McLeod b St Ann's 1843 - d 1927 Sydney, a widow.
The family is listed in Sydney in the 1901 census as McKaskel and again in 1911 as McAskill.
There is some evidence that his father was Murdoch, but it's pretty hazy.
Can anyone point me at Lauchlin's pedigree, any siblings or any other useful bits?