The Baxter family appeared in a developer's walkthrough for The Sims 2. It consisted of Don Baxter, his wife Sarah Baxter, and his son Alex Baxter. Their extended family included Sarah's single sister Virginia, and her father, brother and deceased mother whose names are unknown. There is a family snapshot of them in The Sims 2 game files, hinting that they may have been originally playable. Another hint toward this is the description for Waterside the neighborhood they reside in survives in Neighborhood manager. Sims 2 Trailer
Jill Simon is a 4-star celebrity Sim that was rumored to be featured in The Sims 3: Late Night, in its new city, Bridgeport. She was supposed to live with two other Sims in a luxurious mansion with a curved pool in the hilly, more luxurious section of the city, which is away from the "city center" that is featured very much in the previews. However, neither Jill, nor the household were featured, and the mansion is actually Matthew Hamming's residence. It's possible that she was created for previews.
Amy Star is a Sim that was rumored to reside in Bridgeport, the new neighborhood that is expected to ship with The Sims 3: Late Night. She has been briefly mentioned in a Gamesradar Late Nightpreview with Grant Rodiek, as a target Sim for a vampire, however she was not included in the neighborhood when the game came out. She is a proven fake now believed to be Emmy Starr.