Rugrats/WMG

Brain damaged adults can understand babies in the Rugrats-universe
Judging by the episode where Stu hit his head and thought he was a baby.

Stu Pickles worked for or was an engineer of an R&D Department of a military branch
How else could he have got the funding for let alone the technology to make toys that had thermal sensors?!
 * Not really, you can buy thermisters ten a penny (well not literally, but they are cheap) from any electronics hobbyist shop. Infra-red cameras are surprisingly cheap as well.

Barney is real
Chuckie's supposedly imaginary friend from the episode "My Friend Barney" really was an invisible boy who lived in a castle and went to "prisom" because he didn't eat his vegetables.

Didi is half-adopted.
That is, one of her parents is her step-parent who adopted her after marrying her biological parent. Her younger brother Ben who appeared in two episodes is explicitly stated to be her half-brother. Additionally, while Ben resembles both Boris and Minka, Didi's thin frame and small facial features are nothing like the rest of her family. Because she shares curly hair and a need for glasses with Minka, it's probably Boris who is the step-parent.

THIS is the word Angelica kept using in the Miss Carol episode.
It fits into "[Miss Carol] thinks we're all little _____!!" and, well, the other curse words just don't seem strong enough for Angelica's parents to be so shocked as to not even tolerate her ignorance of what word it is, or even to want to think about it. Also Rule of Funny.
 * I always thought it was this one, because it fits the covering noises better and it's the most commonly used of the main curse words.
 * Since it was in reference to the kids "Little...." it was probably either Little Cunts or Little Shits

Rugrats are the characters from Kill Bill as children.

 * Think about it for a minute. Angelica is The Bride, Suzie Carmichael is Copperhead, Lil is Elle Driver, Kimmi is Oren Ishii, Tommy is Budd, and Dil is Bill. Angelica's crazy as it is, Kimmi's Asian and not from the US, Suzie's black, Lil at the beginning of the series was the only other female peer, and Tommy and Dil are brothers.
 * The crazy 88 are the Mr. Friend dolls.

Charlotte had an abortion in the episode "Angelica's Worst Nightmare."
Just from the way she says "Mommy went to the doctor this morning, and... she's not going to have a baby after all." She also got a lot of pressure and Angelica begging for her to not have the baby, and why would the doctor just think she was pregnant when she wasn't (unless it was the same one that thought Angelica "Peaches" broke her leg...)? Also Rule Of Dude, Not Funny.
 * She could have just had a miscarriage, you know.
 * Wasn't that Charlotte's first trip to the doctor since taking a home pregnancy test? I always just figured she'd gotten a false positive on the home test.
 * False positives on home pregnancy tests are pretty uncommon. Though, given the target audience, they're probably much more likely to imply that's what happened.
 * It's possible it wasn't an abortion, but this is made even more plausible when Charlotte and Drew are discussing finances, and Drew expresses concern.

Dill was originally intended to have some form of mental retardation.
In the first movie, after he's born, all the newborn babies in the hospital are, like the Rugrats, able to talk to each other. Dill does not speak at first, and then barely ever communicates anything to the other babies for the rest of the series. He's a baby even to the babies. The All Grown Up series issued a Retcon, making Dill just "weird" instead of mentally disabled.
 * Also, this is sort of canon, considering the line in one episode of All Grown Up where Lil said something along the lines of "I wonder what Dil would be like if we hadn't dropped him on his head" while Tommy was spying on them with his digital camera ( It Makes Sense in Context )

The babies in Rugrats don't exist and are products of Angelica's imagination because her mother ignores her and her relationship with her father is shallow and parasitic.
In reality, Chuckie died along with his mother, which is why Chaz is such a nervous wreck. Tommy was stillborn which causes Stu to sit in the basement making toys for his son that never had a chance to live, and the DeVilles had an abortion. Angelica couldn't decide whether the unborn child would be male or female and thus simply invented the same character in her head twice with different genders.


 * This makes a lot of sense if you consider the insane adventures that the babies have, mostly when Angelica's not around--they do things that would kill any normal baby, and their parents never notice they've gone missing. Imagine that the babies are toys Angelica plays with when she's at her aunt and uncle's, and when she's not there she's imagining them having crazy adventures. When she is there, she's mostly in charge of the situation.
 * Also, Doctor Lipschitz and the psychiatrist the family visits in "Mama Trauma" are actually specialists helping Didi deal with the loss of her child, rather than a child pyschologist. After all, a woman who is so obsessed with her child's actions that she would drag him to a shrink doesn't seem likely to let that same child wander out of her sight constantly.
 * Angelica's manifestation of white guilt: Susie, the first black Rugrat, is, more or less, the exact opposite of Angelica.
 * Alternatively, it's possible to read Angelica as a tragic figure in the grip of the dark feminine power, while Susie can be explained as the 'light alter ego' that Angelica doesn't consciously know she's lost access to. To Angelica, Susie is the kind of girl she imagines she'd be if she actually had the love and support of her family - while Angelica controls the imaginary Rugrats and attempts to dominate them, Susie is what Angelica might have been if she'd had the chance to love and be loved instead of immersing herself in make-believe.
 * Damn it...
 * sorry to be a jerk but I need to ask if that was true than why can the Rugrats be seen without Angelica?
 * Because Rule of Empathy.
 * No, Tommy's obviously the main character of the show. If anything,

Tommy's the only real Rugrat. The others are imaginary.

 * In psychological terms, Angelica is Tommy's id, Chuckie is Tommy's ego, and Susie is Tommy's superego. Phil and Lil represent Tommy's gender confusion, since he doesn't really have any Tertiary Sexual Characteristics and is too young for a sexuality. Dil is Tommy's inner child, his desire to be innocent and 'normal'. Kimi is his desire for real friend, shaped by Kira's appearance. The parents are just friends of Tommy's parents and any mention or talking to any other rugrats is imagined by Tommy, as are any adventures without Tommy. Tommy's just a lonely kid with loony parents.

Tommy is Jean-Luc Picard
During the events of the episode "Toy Palace" (Where Tommy and Chuckie are locked inside a toy store after hours), the series forks into two Alternate Universes; one where both Tommy and Chuckie are reunited with their dads, and one where only Chuckie is, as Tommy stumbles into the fully functional toy time machine and is sent forward in time to several years after the events of Star Trek the Original Series; where he's taken into the care of a new family, takes on a new name given, and grows up to be the captain of the Enterprise-D.

The Rugrats really were taken aboard an alien spacecraft.
At the end of the episode, the younger characters were shown to be in bed when Angelica was on a desert planet. This could also explain the show's declining quality because all episodes after that are the increasingly incoherent fantasies of a three-year-old who is slowly dying of dehydration.

The parents of the title characters initially had the same dynamic as their kids when they were babies.
I was just thinking about it and realized that you can distinctly see the relationship between the adults too. It could make a lot of sense if they all were just sort of the same dynamic when they were younger even if the roles don't plot out perfectly to their children so the Rugrats themselves are sort of like a repeat generation with these roles;


 * Tommy-Betty
 * Chuckie-Chaz
 * Phil and Lil-Stu and Drew

The only problem I run into is that I can't find an Angelica in the parents' group.
 * Charlotte?

Tommy is a Time Lord.
Really? Nobody's suggested this before? He even has his own screwdriver!
 * THE PLAY PEN IS HIS TARDIS!

All Growed Up is different from All Grown Up because that's how the babies wanted to be when they grew up
They explains the plot differences, voice differences, and personality differences. However we don't always grow up the way we wanted to.

Stu occasionaly sells some of his inventions
To A.C.M.E. It would wrap up nicely why, with his crap job, they still live like rich middle class. One customer though.

Charlotte is having an affair with Jonathan
And Angelica's biological father is Jonathan, not Drew. Drew is completely aware of this because he has never consummated his marriage and Charlotte is a beard. Drew is gay after all.

Grandpa Lou Holds the Democratic Party responsible for his wife's death
In the episode where Tommy is kidnapped, Lou is reading the newspaper and angrily blurts out "Dad-burned Democrats". In a later episode which deals with Stu and Drew as kids, Lou casually mentions their mother was away working on the Presidential campaign of Estes Kefauver, a Democrat who ran in the primaries against Adlai Stevenson. One can easily assume that his wife was a stressed out, politically active Democrat. Since we have no timeline for her death, it can reasonably be assumed that her death could have been caused by stress induced heart trouble. Grandpa Lou then transferred his anger over her untimely death to the Democrats.