Looking for Any Information on John Walpole Married IN Australia IN 18

John Walpole,(1) a convict m to Elizabeth came to Australia on the MARQUIS CORNWALLIS in 1796, received an absolute pardon in Sept 1811.
In 1917 a John walpole (2) died in Sydney, Australia.
A John Walpole (3) was baptised in1797 which was registered at the East India Co's British chaplaincy in Lisbon portugal.
I am researching Dr Henry Nagle walpole m Maria Jackson while serving with the East India Company in Calcutta, I believe him to be the brother of John 3.Henry died in Australia in 1870s.