Abhimanyu was the son of Arjuna and Subhadra. He was a member of the Kuru dynasty. He was heir to Hastinapur until died during the 13th day of the Kurukshetra War, at the age of 16. His son, born after he died, Parikshit, became heir, and eventually king, in his place.
In a version of the story, Abhimanyu is a reincarnation of one of Chandra's sons. Because the Moon god did not want to be departed from his son for so long, Brahma agreed that the reincarnated spirit would only live for sixteen years.