Hi,
Did you have any luck reseaching this line any further?
This is my family also. Thomas and Tyrrell are my great, great, great grandparents on my mother's side.
Their daughter Rebecca, was the mother of Benjamin King who was the father of Ronald Johnstone, my grandfather. Growing up we were told we were related to Tommy Tyrrell, who was a bushranger. I wonder if this Thomas Tyrrell could be the same guy.
I'd love to hear if you managed to trace this any further, as I'm stuck at the same spot.
Thanks,
Kristie