In Monsters, Inc. (2001), Randall tells Sully he heard that humans skin monsters and use their skin on the tops of their toilets. In this film, when Bonnie is in the bathtub, Sully's fur can be seen on the toilet seat cover.
When the toys are crying over bath time being over, one of them says "no more tears!" the phrase seen on children's bath products which indicates that it won't hurt their eyes.
This movie had music from the original 3 movies by Randy Newman
The first of the Toy Story Toons not to feature a post-credits scene.