Not sure if I've answered your posting by direct email - it's been a while since I've been able to get back into genealogy.
I'm the only Hernon from my close family that I know of in Australia - but my parents only migrated here in 1950.
My grandfather John Hernon was born in Birr, Offaly, Kings County in the late 1800s.
He married my grandmother Josephine Sheridan in the very early days of the 20th century - they went on to have seven children John, Molly, Edward, William, Gerard, Kitty and Rose (who died at age 12).
He fought, and was wounded, in WWI then moved to England to be near his sister Brigid (Bridget?).
There are comparitively few cousins, considering they were all devout Catholics! I guess several just didn't get married.
Molly became a nun. John and William went to Canada when William was very young. Gerard stayed in England and became a teacher/tutor/lecturer ... well an educator, anyway. He married but had no children.
No idea what happened to Kitty, but the few old photos I have of my grandmother show Kitty always nearby and wearing sunglasses (in Britain!?)that indicate she may have had a sight problem.
My father married in England and had two sons, my brothers, and they then all came to Australia where I was born a few years later. We then went to America where I grew up, returning here in the early 1970s. Now I live in the Whitsundays. My brothers live in Canada and the US.
We thought John had no children until four Canadian sisters in their 50s and 60s contacted my brother (in Red Deer, Alberta) saying John had been their father but had deserted the family. (Wow, a skeleton in the cupboard at last!)
Well, Rosilea, that's about it.
All the best,