Tracing my ancestors and any living descendants

My maternal grandmother was Margaret Jane Gallagher, born in Derry at the end of 1888; she had two older brothers, Joseph b. 1879 and John b. 1884. Their parents were John Gallagher and Rebecca nee Weir, who married in the Greenbank Presbyterian Church on 14 February 1878. Rebecca's father was shown as Joseph Weir, farmer of Mullougheagh and John's father was also named John, occupation mason of Carey. I have not been able to find those place names, but a local person at Iskaheen recently told me that Carey was probably Carry, near St Patrick's RC Church at Iskaheen (as he was from there himself). The attendants at John and Rebecca's wedding were Robert Joseph Weir and William Weir, and I think they were Rebecca's brother and ? cousin respectively. I think Rebecca may also have had an older sister, Margaret who may have married a person with the surname Allen, and I believe John had a much younger sister, Margaret Jane, baptised Dec 26 1862 in St Patrick's RC Church, Iskaheen (mother's name given as Mary Elder, but on John's death in 1928, his son Joseph was the informant, and gave the name Margaret). On Rebecca's death in 1902, the informant, her husband, John, recorded her (deceased) mother's name as Rachel, nee Weir. Joseph Weir, her father, was also shown as deceased.

The local person at St Patrick's RC Church at Iskaheen did tell me that there is a Weir family living at Glackmore and an Elder family still living at Burnfoot. I would dearly love to hear from anyone connected to me.

With thanks.  Helen Thomas