Hi Anne
Welcome to Ireland Reaching Out!
The best thing to do might be to have a look at familysarch.org for records of the Sorahan family in Cavan. If you can make sense of what you find there and any potential children of John's siblings (if there were any, and assuming they all stayed behind if they did exist).
As family search is free you will be able to have a good look before perhaps moving to subscription sites to verify or double check any additional info you find.
There are a good lot of Sorahan records for Cavan on the site
Best wishes
Clare Doyle
Genealogy Support