Alexios Komnenos, latinised as Alexius Comnenus (Greek: Ἀλέξιος Κομνηνός; October 1106 – summer 1142), and sometimes called Alexios the Younger, was the eldest son of the Byzantine emperor John II Komnenos and his wife Eirene of Hungary. He was crowned co-emperor in 1119, at 13 of age, but predeceased his father in 1142. He was an elder brother of the emperor Manuel I Komnenos, and had a twin sister, Maria Komnene (plus other siblings).