His union with Aldona had produced two daughters, Elizabeth (1326–1361) and Kunigunde (also Cunigunde; 1334–1357), but no male heirs.

Adelaide lived primarily at the castle in Żarnowiec on the Pilica river and is credited with founding the parish church there.

Casimir separated from Adelaide in 1356 and entered a morganatic marriage with his mistress, Krystyna Rokiczana (also Christina), the widow of Mikulasz Rokiczani (also Miklusz, Mikuláš), a wealthy merchant.

Casimir's separation from Adelaide was not recognized by the church and was considered bigamous, which put him at odds with the clergy.

Casimir continued living with Krystyna despite complaints by Pope Innocent VI on behalf of Adelaide.

Casimir managed to have two of his daughters, Anna and Kunigunde, legitimatised by Pope Urban V on December 5, 1369.