Salo Fiszgrund with his first grandson, Janek Rutkowski

This is Salo Fiszgrund with his first grandson, the son of Jerzy Rutkowski, named Janek. The photo was taken in Warsaw in 1955. Salo Fiszgrund had two children with his first wife, Julek and Hanka. Both were born in Cracow. Julek was one year an a half younger than me, so he must have been born in 1923. Julek Fiszgrund changed his name to Jerzy Rutkowski after the war. It seems to me it was the name by which he went during the war, but I'm not sure. Julek secured a PhD in Leningrad, then a post-doctoral degree, and soon after returning to Poland started teaching law at the Warsaw university. It seems to me it's four or five years since he died.