Hi Bronwen
Not a lot of help I'm afraid.
No Rubbathan listed at all, but variations of the name include Robotham, Robothon and Rowbotham.
Not sure whether you have ever come across those spellings in your research.
The following are who are recorded
Oliver Robotham of great age 10 March 1667/8 but doesn't say where buried, just in the Parish of Llanbrynmair
Oliver Robothon 23 November 1691/2
Frances Rowbotham relict of Oliver Rowbotham deceased 7 April 1671/2 maiden name could have been Tart buried in Pennant
John Ralph (alias Robotham ) 29 August 1718
Sarah Ralph (alias Robotham ) 19 December 1718
Sorry nothing else after that unfortunately
Maybe the local Family History Society has more records that would help, always very knowledgeable there.
Good luck and enjoy your visit.
Erika
