Yesterday I referred you to Kyle J. Betit’s two articles: in The Irish At Home and Abroad journal. In review, these are “Researching Catholic Nuns, Brothers and Priests in the U.S. for Place of Origin” (Volume 4, #3 (1997), pages 121-125); and the second is “Priests, Nuns and Brothers in Ireland” (Volume 5, #2 (1998), pages 70-76). Become well acquainted with these articles.
The point of researching a woman religious is because it is within the records of her life you may find where the entire family was born in Ireland. Women religious are very important females in your family tree.
Religious orders for women were very popular among the Irish in both Ireland and abroad. Sometimes it seems like there was always one girl in an Irish Catholic family who joined a religious order. Each order had an abbreviation, and this is important. For example BVM stands for Sisters of Charity of the Blessed Virgin Mary. OCD means Order of Discalced Carmelite Nuns. OSU means Order of St. Ursula (Ursuline Nuns) and RSM means Religious Sisters of Mercy. If you see these initials associated with a religious woman relative, this identifies the order name.
If you do not know what order a young woman may have joined, then look at her home parish. What order served it or the school she may have attended? A young woman was very likely to join the order of the nuns serving her parish or school.
Once you have an order, then you are ready to search for the records kept by that order which trained her. Sometimes it’s as simple as an Internet search.