Looking for Annie or Anne O'Brien or Brien

For many years, I have looked unsuccessfully for my 2xgtgm Annie O’Brien, born between 1833 and 1838 to Michael O’Brien and Mary McDonald in Cootehill, Co.Cavan.

Recently I found an Anne Brien baptised 7 April 1836 to Michael Brien and Mary Brien of Stratford, Baltinglass, Co.Wicklow.  Sponsors were Thomas McDonnell and ? 

The similarities are too numerous to ignore.

Does anyone have information on the Brien family and can I claim to have found Annie?

Jocelyn