Reese

An android with a child's consciousness. She created the Replicators for her to have as toys, but she lost control over them and her whole planet was destroyed. She was taken to Earth by SG-1 before they realising what threat she was. She made a good, though somewhat jumpy, connection with Daniel Jackson whom she started to regard as a friend. She was killed by Jack O'Neill when the base were attacked by the Replicators, but before she died she shut the newly created Replicators off. (SG1: "Menace")