Hi Rab,
The only info I could find is on RootsWeb's World Connect Project (follow the link below). The siblings names are private but you could email the site manager explaining your connection.
email: rabann@cableinet.co.uk
Parents and spouse names are provided.
http://wc.rootsweb.ancestry.com/cgi-bin/igm.cgi?op=Search&includedb=&lang=en&ti=&surname=martin&stype=Exact&given=edward&bplace=letterkenny&byear=1900&brange=2&dplace=&dyear=&drange=0&mplace=&myear=&mrange=0&father=&mother=&spouse=&skipdb=&period=All&submit.x=Search
Regards,
Kevin
