Stewart Nelson Irwin 1916

I'm trying to find out any information on my Great Grandfather. He was Stewart Nelson Irwin. He went to WW1 but was killed in action in 1916. He was married to Ethel Mudie, they had 5 children. As far as I know all the family moved to Blackpool England but my grandmother returned to Enniskillen Co Fermanagh Norhtern Ireland.
I would also like to find any information on Ethel Mudie or any of the Mudie family. Ethel was the daughter of Sir Edmond Humphery Mudie. Sir Edmound was born in Venice in 1839 and moved to Dublin Ireland sometime later, he died in 1896.