Both my grandfathers were 14 years old when WW1 ended and there were Britishsoldiers of that age serving in WW1, I believe, against all the rules, but not my grandfathers. Wind forward to WW2 and one grandfather was in a reserved occupation working above ground at a coal mine and fire watching on roof tops when he wasn't doing that. My other grandfather was also in a reserved occupation of being the only qualified electrical engineer in the Clacton area to service air raid sirens. He was also in the Home Guard and Civil Defence. Both grandfathers were at the upper end of the age bracket for conscription by WW2.