Bagot (Baggot) and Fleming families near the Co. Roscommon/Co. Galway border

I am interested in information on Henry Bagot (born about 1800-1810) and his wife Catherine (born about 1810).  In July 1836, Henry co-signed a loan, and was listed as living in Treanboy, Kilcroan, Co. Galway. However, the Bagot (Baggot) name is seen across the border in Co. Roscommon, including Cloonreliagh, Killtullagh. As well, Henry Bagot or his wife Catherine seem to be related to the Fleming family in this area. In Nov. 1837, Henry was a godfather to the daughter of Richard Fleming and his wife Mary Feeny, of Killbegnet and Dunamon, and my Dad has DNA matches to Flemings from this area.

Any information is greatly appreciated, especially which parish(es) records to search to find the baptismal records of Henry's children. There were at least 3 sons born prior to the family emigrating to London about 1848.