Alternate timeline(covers information from an alternate timeline)
Ensign Nell Chilton was the flight controller aboard the USS Pasteur under the command of Captain Beverly Picard in an unknown, future timeframe.
Chilton was killed during an attack on the Pasteur by several Klingon attack cruisers, when the helm console exploded. She was the only casualty before the ship was rescued by Admiral Riker and the USS Enterprise-D. This timeline was replaced by a new one where the anti-time eruption never existed. (TNG: "All Good Things...")
Chilton was played by Alison Brooks, the girlfriend of producer and writer Brannon Braga at the time.
Chilton may or may not exist in the "real" timeline; if she did, she was probably a young girl or not even born yet at the time of "All Good Things...".