Repented Sinner
Sid learns an important lesson in the first Toy Story: don’t mess with toys. Since Andy and his family move away from their home in the first film, we don’t see Sid in the next. However, there’s someone in the Toy Story 3 that could very well be Sid.
In the third installment of the four-part film franchise, we see a garbageman sporting a skull on his t-shirt that looks a lot like the same shirt Sid used to wear in the first film. Not only that, but the voice actor for Sid in the first movie, Erik Von Detten, would return for Toy Story 3 and provide the voice for the garbage man in question. Also, the filmmakers confirmed this theory.