Praiseworthy was a young child who was part of a crew of human colonists who settled on the planet Gliese 581 D in the far future. His mother was part of the set-up team who were awoken from stasis before the rest of the colonists to ensure the city was working properly.
When the Twelfth Doctor decided to blow up the colony without knowing the other humans were still in stasis, Bill came across Praiseworthy, who had just woken up. The Doctor quickly repaired his sabotage and while no one was looking, Praiseworthy went outside to look for his mother. However, he instead encountered an Emojibot who gave him an mood badge. When he realised his mother was dead, the Emojibots seized him and prepared to kill him as he broke down in tears.
In an attempt to save him, Steadfast shot the robots, which angered the Vardies. Bill protected Praiseworthy from the attacks. Once the Doctor reset the Vardies' systems and erased their memories, an Emojibot offered Praiseworthy a drink. (TV: Smile)