Masaltov and Victor Zadok

This is my grandmother Masaltov Zadok and her son Viktor Zadok, so basically my mother's mother and her brother. I think they are in Serbia, in Rogaska Slatina, where they went for a holiday. The picture was taken in 1934 because behind it, it says 18.VIII.1934. My grandparents went almost every year, sometimes my uncle and his family went, too; my family never went. My grandmother is wearing black not because she is in mourning but because she wore it a lot. My grandparents, my uncle’s family and my parents all dressed in a more European than traditional way.