I too have several relatives who came from Kapyl to Sioux City, Iowa.
They were siblings: Shmerel PASSMAN and Chaya (Passman) HARLOW.
They were the children of Yekusiel and Finkel (Perlman) PASSMAN. My husband is a descendant of the Perlman family which was numerous in Kapyl.
There were a number of other siblings who remained in Kapyl, one of which had a son who assumed the surname of SHAPIRA and emigrated to Israel after WWII.
This is the first I have heard that many Kapyl former residents had gone to Kapyl. We always wondered why these relatives wound up there.
I have traced much of the rest of the PERLMAN family, but never tried to find out more of these Sioux City relatives