Goodthing

Goodthing was a human colonist of the far future who lived in the colony planet Gliese 581 D.

She was among the set-up team who were awoken from stasis to make sure the city was functioning properly. At some point, she discovered her mother and several other colonists had been killed by the Vardies but she realised that it was because they showed negative emotions such as grief.

When she desperately tried to warn Kezzia about the deaths and told her to keep smiling to avoid the same fate, she could only watch in horror as Kezzia was ripped apart by the Vardies before she became their next target. She was then killed.

The Twelfth Doctor and Bill later came across her remains, along with the bones of the other colonists who had been turned into fertiliser. (TV: Smile)

Trivia
In a deleted scene, Goodthing is seen evading the Emojibots by hiding in the botanical gardens. But when she turns around she is faced with an Emojibot that kills her. It can thus be speculated that while she initially managed to flee from the Vardies after they killed Kezzia, she was ultimately killed offscreen.