between 1253 and 1254, barnim i married secondly with margareta (b. aft. 1231 – d. bef. 27 may 1261), probably a daughter of nicholas i, lord of werle and member of the house of mecklenburg, although other sources identified her as a daughter of otto "the child", duke of brunswick-lüneburg. historian robert klempin identified her as the widow of vitslav i, prince of rügen, but this seems very doubtful from a chronological view. they had one son: