Hi Kev/Mervin
Many thanks for your comments. One thought that did occur to me , did the 'management' of the National Volunteers issue any 'commemorative' medals for any purpose? An article in Freemans Journal for 20 April 1915 records that a L/Cpl in my grandfathers company (F Coy, 2nd Batt, Dublin Regiment INV) left Dublin to join the 8th Batt, Royal Dublin Fusiliers at Buttevant wearing his INV uniform - perhaps 'other medals' could have been worn with permission?
Re the smile, I remember my father saying that his father had an 'impish' sense of humour.