Thanks for all this.
No, I haven't traced a medal index card.
I believe his father was Samuel Harris and his mother Emma Harris nee Bate, but as I haven't been able to find a birth record I cannot definitely prove this. Birth place was West Ham or Clerkenwell. I got GRO to check a year either side of 1893 with no luck. He was married to Emma Florence Savage in Dec 1911.
Where did you find that he was discharged from Royal Sussex Regiment 26 September 1916? Would that mean he was injured as he was discharged before the end of the war?
I am very grateful for any help.