Hi Mary - Your post is nearly 10 years old so I don't know if this will ever reach you. But, anyway if you do get this, I'd love to hear from you. I'd be particularly interested to know if you knew if Maurice Dinan had any Brothers.
My surname is Dinan and I live about 2 miles from the Townland of Ballycugguran. So chances are that my family originated from the same Dinans as Maurice with my Great Great Grand Father possibly being a Brother of Maurices.