Miley family of Rathdrum

I am trying to trace my Grandmother Julia Miley. She died in Lancashire England in 1925 when my father was three & he was told very little about her . She married my Grandfather, William Day, in Lancashire in 1920 & on the marriage certificate she gave her father as James Miley, a farmer, deceased. On the 1921 census of England she states that she was born in Rathdrum, Co Wicklow & is aged 26 years 6 months (therefore born end of 1893 beginning of '94) On numerous websites ( irishgenealogy, family search,ancestry)I can find no record of her birth.Parish registers of Rathdrum for this period are not held at the NLI, can they be seen elsewhere? The only Julia Miley in the Rathdrum area on the 1901 census of Ireland is at Knockrath, living with a family named Connolly who from a newspaper item were her foster parents A James Miley on the census is at Ballydonnell with his wife Margaret, no other children, he died in 1902. All listed as R.C. He is one of ten children born to John & Mary Miley, farmers at Cullentragh Rathdrum. My questions are: Where else can I try to find her birth,where can I find details of why she was in foster care & for how long & does anybody out there have any knowledge of the Mileys of Rathdrum. With so many siblings to James I am hoping that there are still some decendedents out there. Thanks in anticipation