Hello Jenn, I have recently started to trace my family tree and I think that my wife,Liz,might be connected to you. Liz's maternal great grandmother was Esther McMahon from Tamery,Hilltown,County Down who married Samuel Cromie from Barnmeen,Rathfriland,County Down. No dates yet, but must be mid-late 1800's. Your Mary Jane McMahon might have been a sister of Esther. Liz's paternal great grandmother was Eliza Jane Truesdale born 1847, from Ballynagappog,Rathfriland,County down. Eliza Jane married Robert McIlroy Young in 1874, who lived at Annahinchago. I have not,as yet,found the names of William George Truesdale nor Joseph or Isaac but Eliza Jane married into the Young family from Annahinchago,Katesbridge,Banbridge,County Down, a place which you mentioned.