Thanks Frances. Hugh's 2nd wife was from Ireland so he could well have been Catholic too. I will probably leave Hugh now as it looks like he is not a Cavendish and therefore not in my family tree. It's good to have a puzzle 'solved' (I hope!) even in a negative way. Perhaps someone looking for Kavanaughs might find it useful.

One thing though - I would value your opinion on whether it's a mistake to think that the John and Thomas Cavendish mentioned in my first message (Thurs 1.52 am, #524302) in the family of William Cavendish & Jane Rowland, could be the same person?