Despite the protagonist of Portal, Chell, being seldom seen by the player, she quickly became a fan favourite. For the most part, Chell is your only human connection as you journey through the elaborate and treacherous tests that GLaDOS sets up for you; no wonder we all get attached.

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Though we all love Chell, we don't actually know very much about her. One closely guarded secret is her parentage, and the most popular fan theory about it speculates that Chell's parents may have worked at Aperture. What proof is there? That's what we're here to explain.

Why Chell Is Thought To Be The Daughter Of Aperture Scientists

Very little is known about Chell's backstory. The game doesn't give us any information - she's just thrown into the tests after waking up in the Aperture Science facility. In any place it would normally appear, her surname is listed as [Redacted].

We do know a little more, assuming you're comfortable trusting GLaDOS. She says that Chell was abandoned at birth on multiple occasions. She also says mentions that Chell was adopted. Finally, there's one moment where GLaDOS mentions that two people with the same surname as Chell are in cryogenic stasis. If her previous statements were true, these two people would presumably be Chell's adopted parents.

The theory that Chell is the daughter of two aperture scientists existed for a long time, but really took off after the release of Portal 2.

The key evidence was that, while exploring old parts of the Aperture Science Enrichment Center, you can discover a forgotten 'Take Your Daughter To Work Day' event, with various science projects made by the daughters of Aperture Scientists. One of the boards includes the note "By: Chell" (see above). Seeing as Chell is a fairly uncommon name, fans took it to indicate that this Chell is the same as the player character.

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Fans also believe that Chell being the adopted daughter of Aperture Scientists would explain why she was a test subject in the system. Just before GLaDOS was turned on, Aperture Science had begun encouraging its scientists and their families to become test subjects. This was due to their inability to pay anyone to be their test subjects anymore, as the company was in a terrible position, financially.

Is Chell Caroline and Cave Johnson's Daughter?

Some fans take this theory one step further by suggesting that Chell might actually be the daughter of Cave Johnson, the CEO of Aperture Science, and his assistant Caroline (who eventually became GLaDOS).

To start, Caroline (as she appears in the oil painting with Cave Johnson) bears a resemblance to Chell. It also makes sense that if Chell's given surname was Johnson, it would explain why it was redacted in Aperture records, lest anyone become curious or suspicious when reading Chell's file.

Assuming that Caroline and Cave felt the need to give Chell up because they were not married (since their marriage is, at least, never mentioned), allowing two Aperture scientists to adopt her would mean that Caroline and Cave wouldn't have been out of Chell's life entirely.

Then, in Portal 2, GLaDOS becomes far more friendly with (and even defensive of) Chell after the revelation that she was once Caroline. We also see Chell's potato project in Portal 2; her potato, unlike all the others, has grown to a tremendous size. Some fans suggest this was because her parents - the leaders of the company - were able to give her something special to dose her potato with and ensure that she would win.

Another fairly convincing point is made during the final credits of Portal 2, when the turrets perform an Italian aria for you. The lyrics were partially improvised, but (when translated into English) they refer to Chell as:

• "my child"
• "my dear"
• "my dear child"
• "my darling beauty"
• "my beloved"
• "my little girl"

The lyrics also tell Chell to "walk far away, so far away from science," which may be a message from GLaDOS (who has now reclaimed her memories of Caroline) to run away from the dangers at Aperture.

Finally, we must consider the people in cryogenic storage with the same last name as Chell (if we assume this isn't just GLaDOS being cruel). GLaDOS specifically says that these two people, a man and a woman, are test subjects in cryogenic storage.

While this is a little bit harder to explain, some people have suggested that it's possible that Cave Johnson's body was cryogenically frozen in case they might one day discover a way to bring him back to life.

As for Caroline, they suggest she might have married Cave Johnson later in life, and note that it's unclear what happened to her after she became GLaDOS. It's entirely possible she was also frozen in case her brain was ever needed for some reason while the scientists worked on GLaDOS.

Either way, it seems clear that the developers want us to think Chell is connected to the facility somehow, and are playing coy with the details.

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