Taking another look at this side of the family after a break... I looked at the image of Ann Brien's 1831 baptism and the abode for her parents, Michael Brien and Ann Doyle, was Drumphea which is part of the Myshall parish I believe?
There are definitely no other children born to Michael Brien and Ann Doyle but there are children baptised at Myshall to Michael Brien and Catherine and Mary Doyle:
17 November 1839, Thomas son of Michael Bryan and Catherina Doyle
5 May 1841, Brid(get) daughter of Michael Brien and Mary Doyle, abode "Nockendrane", think this should be Knockendrane
February 1842, Edw. son of Michael Bryan and Catherine Doyle
Could it be possible that Ann Doyle was the same person as Mary/Catherine Doyle? I know it's a bit of a reach but I thought I would consider it, simply because of the shared surname. I'd just like to hear people's thoughts on this.