Pixar is no stranger to placing Easter eggs in their movies from some of their other releases, and Toy Story 4 has two possible cameos from Monsters, Inc. character Boo. The latest installment in the Toy Story franchise follows Woody (Tom Hanks), Buzz Lightyear (Tim Allen), and the gang as they welcome a new addition to their loving bunch, Forky (Tony Hale). The group sets out on an adventure as they attempt to rescue Forky, who's dealing with a bit of an existential crisis. Toy Story 4 reviews have praised the movie for its lovable storyline, superb animation, and for tackling a complex theme about identity and purpose.

In true Pixar form, Toy Story 4 also included plenty of Easter eggs and nods to some of their previous works. Easter eggs have become a fun part of their movies for audiences to seek out. One of Pixar's biggest Easter eggs is A113, a reference to the classroom at the California Institution of Arts that fostered the up-and-coming animators who would go on to create the mega-successful animation studio. Many Easter eggs have also prompted the creation of fan theories, such as The Pixar Theory. But, out of every Pixar film, Toy Story 4 takes the prize for having the most references hidden inside the movie's quaint little antique shop.

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The cameos don't stop in the antique shop, though. There are a couple of potential appearances from Pixar's lovable monster movie, Monsters, Inc. One of the cameos is of a little girl from Toy Story 3, who many fans theorized to be Boo from Monsters, Inc., who makes an appearance in Bonnie's kindergarten class. Another shot from the film also featured a young girl with pigtails in a pink shirt who tries to win the series' beloved newcomers, Ducky and Bunny. Check out the image of a possible young Boo in Bonnie's class below:

If this were true, it wouldn't be all that surprising. Incorporating Boo into this movie makes for a fun Easter egg that's also a little harder to find while also adding more fuel to the Pixar Theory fire. With Toy Story 4 having been written while the third installment was still being finished, it left a lot of open time to include a few more well-hidden nods to previous films. It also shows that the writers know what their fans enjoy seeing, which could be why they included references to Toy Story 4 in other Pixar movies long before it even hit theaters.

Pixar's hidden references to their films is not only a fun aspect of their movies for viewers to jump in on, it shows how much they love the work they do. Easter eggs are oftentimes a magnificent way to show appreciation for their fellow animators and the work that they've put together. Whether or not the films all share a universe, the writers love to keep people speculating. And even though Toy Story 4 will be the last sequel from Pixar for awhile, its nods to previous films serve as a celebration of the work that Pixar has created thus far, and how their journey is far from over.

Next: Toy Story 4's Post-Credits Resolves the Movie's Most Glaring Cliffhanger

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