Who was XXX's mother?
Ma Xisheng
(Ma Yin would eventually have at least 35 sons, and Consort Yuan bore at least one of those of Ma Xisheng's younger brothers, Ma Xiwang (馬希旺), although none of the eventual rulers of Chu subsequent to Ma Xisheng -- Ma Xifan, Ma Xiguang, Ma Xi'e, and Ma Xichong -- was likely born of her, with Ma Xifan and Ma Xiguang clearly born of a different concubine, Lady Chen.)
Consort Yuan