Daniel was the seventh cylon model created by the final five. Ellen referred to Daniel as an “artist who was sensitive to the world”. She was very close to Daniel, which enraged Cavil; he felt that Daniel was Ellen’s favorite and became jealous. Cavil poisoned the amniotic fluid being used to mature the Daniel copies and then corrupted Daniel’s genetic code. This sabotage meant that no further Daniel copies could be created. It is unknown if any pre-existing Daniel copies survived Cavil’s actions, or for that matter if any Daniels were grown to maturity prior to Cavil’s treachery, for the Sevens were not mentioned again during Battlestar Galactica’s remaining episodes.