Pixar has been around for decades, and we’ve loved every movie they've produced. From watching toys come alive to watching a boy become a ghost, Pixar has given us some incredible characters with extraordinary stories. We find it easy to become enthralled in the unique worlds they've created for us, but for some fans, they believe that there is only one world.

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The official Pixar Theory was first thought of by Jon Negroni, and it has gained a wide following among fans. People who love the theory are constantly rewatching and finding new bits and pieces that fit together to come up with their own theories, and some of them will surprise you. Here are ten theories about the Pixar universe and its films that will leave you speechless.

Randall is Andy’s Monster

Since the Pixar films all take place in the same world, it makes sense that the Pixar children would have monsters from Monsters Inc. who come through their closet to scare them (or make them laugh). Andy from Toy Story is no different. How do we know his monster is Randall? The clues come from three different places. In Monsters Inc, Randall is seen practicing camouflage against a background that looks just like the walls in Andy’s old room. In Toy Story 3, we see a sign on Andy’s closet with a picture of a creature that looks like Randall. The third clue comes from the official Monsters University college website where a door that looks just like Andy’s is spotted. We’re sold!

Riley is Adopted

Pixar has shown us lots of different families, and one of them is the Anderson family from Inside Out. They seem like a typical family, but a lot of people think that Riley may be adopted. Riley doesn’t look like her parents, but that's not the only "proof" fans came up with. One moment we see is that her mom appears to be standing and well put together the first time she meets Riley, not as if she's just given birth.

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Another piece of the puzzle exists in Riley's family island of personality where you can see a family tree. A single person, who we assume to be Riley, exists at the top of the tree, rather than the bottom. This is believed to be the family she imagines to have someday since there is no biological family to exist above her.

Carl Lost His Mind

We all know that Carl from Up took a fantastical adventure by using balloons to float his house to a waterfall where he and his wife always wanted to go. Did this trip actually happen though? Some Pixar fans don't think so. They believe that Carl is delusional and the story we see played out never actually happened. You have to admit, it does seem a little far fetched that he would be able to lift his house with a little over 20,000 balloons (Pixar has given the official number as 20,622); then the house just so happens to float and land exactly where he wants it to go; and lastly, he meets his life long hero who coincidentally is nearby. Does it seem too good to be true? It might just have been Carl's imagination.

Boo is Edna's Daughter

Boo, whose real name is Mary, is a mysterious character from Monsters Inc. that many have been curious about. We know little to nothing about her, but that hasn't stopped fans from finding clues to draw conclusions. After watching Boo seem to have superpowers (like appearing somewhere else really quickly) Pixar theorists started guessing that her parents could be from The Incredibles, particularly Edna, with one of the supers as her father. While Edna has said she has never been "afflicted" with children, it is possible that she birthed one and gave her baby up for adoption. Who do viewers think she gave her child to? The superhero Thunderhead, who Edna has mentioned is good with kids. His file also says that he has adopted five children, one of whom could be Mary!

Andy's Mom is Emily

This is a pretty popular theory among Toy Story fans. In Toy Story 2, we meet Jessie, a cowgirl doll who tells us about Emily, her previous owner. We see that Emily has a dark red hat very similar to Jessie with white rope around the edge. (Woody's hat is brown with brown rope).

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While Andy originally had Woody as a toy and not Jessie, his cowboy hat that he wore as a child looks a lot more like Jessie's and the one that Emily had. Where could he have gotten it from? Fans believe that it was passed down from his mother, aka Emily!

Riley's Monster is George Sanderson

If all children have monsters, that would include Riley from Inside Out. Fans have drawn the conclusion that George Sanderson is Riley's Monster, and it all stems from looking at Bing Bong, Riley's imaginary friend. Bing Bong tells us what he was inspired by, but he fails to mention where his legs came from. Audiences think that his legs must have come from Riley's monster, but this was not listed because Riley could not properly identify what her monster actually was. Looking at Bing Bong's legs, we see orange and yellow stripes, just like George Sanderson!

Onward is Andy's Imagination

We won't be too mad if you've never heard of Onward because it hasn't actually come out yet, but we have seen trailers and pictures. So far, we know that it includes a lot of fantasy characters, which is the first clue that it could just be a make-believe story in the Pixar Universe. The boys in the film are on an adventure in search of magic to bring their deceased father back to life so that they can spend some time with him. Do we know of another Pixar character who does not have a father and has a creative imagination? Andy from Toy Story, of course! Onward could just be a story he imagined to help him cope with not having a father.

The Witch is Boo

We know who fans think Boo's parents are, but do we know anything about who she becomes as she grows up? According to theorists, she is none other than the witch from Brave! Seems like a big stretch? Well, she has an obsession with bears, who Sully seems to resemble, but if that's not a good enough reason for you, the witch actually has a carving of him in her shop.

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Another bit of proof is that on her hut, she has a magic door where things on the other side change, similar to how things can change on the other side of doors in Monsters Inc.

Darla is the Daughter of a Rock Star

We know Darla as the tiny fish killer in Finding Nemo, but she also appears on the cover of a magazine that Molly is reading in Toy Story 3. Why would a random little girl be on the cover of a magazine? She must be famous in some way! When we see her visiting the dentist in Finding Nemo, she's wearing a shirt that says "Rock n Roll Girl," which leads fans to believe that she is the daughter of a famous singer. This makes sense because children of celebrities are often in the limelight and seen in magazines, just like their parents.

Dash is Molly's Father

If you take a good look at Andy and Molly from Toy Story, they don't look that alike. While they share blue eyes, one has an oval face with brown straight hair, and the other has a square face with blonde curly hair. This could mean that they have different fathers. Who else in the Pixar world has blonde hair and a square face? Dash from The Incredibles! Some people may be saying that this wouldn't work because they are both kids, but if you look at the timelines in each movie, it could work. Dash was born sometime in the '60s, while Molly was born around '95.

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