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Pre-1840 there really aren't any useful records for Aghadowey Presbyterian Church. Baptisms don't start until 1855 and there are no burial records (except a later map of the graveyard and notes done in 1950s with the old church sexton). The early communicants rolls have long disappeared. The first Stipend List (showing pew holders) is 1832/1835 (a Richard Roxborough in pew number 141 along with William Roxborough, Jasper Roxborough and John McNeal & Danl McNeal- these Roxboroughs were from Ballynacally Beg). Note: pew numbers are the old ones not the current numbers as the church was renovated before WWI and pews, aisles, gallery, etc. changed. The 1836/1839 list is the same. Next list 1840/1844 shows on William Rosborough, Daniel McNeal and Jasper Rosborough.
Regarding Richard Roxborough and Mary Pedan the marriage supposed to be 1828. Mary died in 1890 and Richard in 1901.
https://civilrecords.irishgenealogy.ie/churchrecords/images/deaths_returns/deaths_1890/06108/4743664.pdf https://civilrecords.irishgenealogy.ie/churchrecords/images/deaths_returns/deaths_1901/05740/4620517.pdf (informant- grdau. Lizzie Roxborough, Bovagh)
I know of five children: James (went to Liverpool, England), John, William, Rachel Brown, Anne.
Pre-registration of marriages (1845) there will be limited details in church records (if such records survive)- usually just date, bride & groom and perhaps name of minister and two witnesses. The marriages for Aghadowey Presbyterian Church only start in 1845.
William Roxborough and Mary Torrance probably married early 1840s as oldest known child born c1841 at Caheny. Known children: James, John, William, Jennie, Mary Ann, Richard, daughter, Samuel. Many of this family emigrated to Allentown, Pennsylvania although some did return to Ireland.