Human civilian, orphaned when his mother, Marla Aster, an officer aboard the U.S.S. Enterprise-D was killed in 2366 on an away mission. Aster's father had died five years earlier due to Rushton infection.
A race of non-corporeal beings known as the Koinonians with remarkable abilities were inadvertently responsible for the death of his mother, and sought to recreate facsimiles of Aster's mother and his Earth home.
Initially preferring to accept the false reality, Aster eventually accepted the truth and became an honorary member of Enterprise-D officer Worf's family, through a Klingon bonding ritual known as R'uustai. After the incident, Aster returned to Earth to live with an Aunt and Uncle.