Sigmund Freud (1856/1939) with his sons Ernst (1892/1970) and Jean-Martin (1889/1967) during the war, where they fought in the Austro-Hungarian Army, surviving the conflict.
Austro-Hungarian assault troops (Sturmtruppen) of a Sturmpatrouille on the Piave Italian Front,, 22 June 1918. Note that only some have rifles and that many are armed only with hand grenades (and probably pistols)
Also of note that some have canvas helmet covers -- the guy in the front seems to wearing some kind of pith helmet?
8 September 1917: Austro-Hungarian Sturmtruppen on the Isonzo Front, during the last days of the 11th Battle of the Isonzo.
Note the grenade bags, full medals worn on combat dress, canvas helmet covers and the variety of shades of field-grey uniforms