Oda of Haldensleben wife "Ote" and her sons by him (Mieszko and Lambert are only named; probably Świętopełk was already dead by that time or was in Pomerania as a ruler, according to modern historians). Mieszko I's oldest son, Bolesław I the Brave, is not mentioned, perhaps because he already received his inheritance (probably Lesser Poland, who included Kraków and some other cities). It's also believed that the document was inspired by Oda, who wanted to secure the inheritance of her sons (with the Papal protection) in detriment of her stepson Bolesław I. After the death of Mieszko I (25 May 992), Bolesław
Mieszko the Younger point, Mieszko III decided to give the district of Kalisz to his youngest son and namesake, as his own Duchy. Mieszko the Younger died on 2 August 1193. He was buried in the crypt founded by his father in the Cathedral of St. Paul the Apostle in Kalisz. Tombstones of Mieszko the Younger and Mieszko III were found during archaeological excavations during 1958–1960. For unknown reasons, Mieszko never married or had children. On his death, Mieszko III give Kalisz to his eldest son Odon. Mieszko the Younger Mieszko the Younger (also known as of Kalisz) () (between 1160 and 1165