This was posted some time ago, so I'm unsure if you'll see this. I'm related to Sarah, Patrick's wife. When they settled here in Australia, they made quite a name for themselves and afterward, bought Sarah's family over.
A google search will show you a little history about their time in 'Armagh' Clare Valley in South Australia. "The last of the butlers" is what you'll want to search.
While there are believed no relatives left for Patrick himself, Sarah's family have a few lines still going, myself being one.
I have been searching more about Sarah's side of the family in Ireland, but cannot get much further than what our family books tell us, that have been passed down in the family.
I hope this gives you some insight into Patrick and Sarah's life here in Australia. If you ever see this.