Chuckie is the third oldest out of the six main Rugrats at two. He is distinguished from the others by his irrational fear of particular objects, most notably the guy on the oatmeal box (a parody of The Quaker Oats man) and clowns. He is also the only Rugrat who is left-handed or south pawed, and the only one, besides Angelica and Susie, who has spoken an intelligible word to adults during the Rugrats series. He said "No" during the Rugrats in Paris movie.
One of the original five main characters introduced in Rugrats, Chuckie has uncontrollable red hair, glasses, and buck teeth. He is left-handed, as revealed in Chuckie's a Lefty. Chuckie commonly wears a blue shirt with Saturn on it, purple square glasses, green shorts with light green squiggles, yellow ankle-length socks and red shoes with untied white shoelaces. While being potty trained, he wore beige, light blue or white bear-patterned training pants, then dark blue or white briefs. He is scared easily, and at the first suggestion that he and the other babies should do something or go somewhere, he will always say, "Maybe this isn't such a good idea." All the same, he is still friends with Tommy and the Phil and Lil DeVille.
He is loyal and often brave, facing his fears to come through for his friends, whenever there's a problem. He is very close to his father, Chas, and is usually the main target of Angelica's bullying. For example, in Chuckie vs. the Potty, Angelica tries to scare him into thinking he will never be potty-trained by turning the water on and off to make him think he has to go when he doesn't. However, this cruelty backfires on her when she has an accident right after Chuckie gets the hang of it.
Chuckie is the only character who does not come from a two-parent house hold. In the Rugrats Mother's Day episode we learn that his mother, Melinda, died from an unnamed illness. In the episode it is apparent that he does not remember his mother. Though he cannot properly communicate with adults, he has been able to say "NO" which the adults can hear. He has nasal congestion problems that make him sound like he has a perpetual cold. The only episode during which he does not talk in a nasally voice is The Smell of Success in which his congestion is cured by Dr. Brander's invention, The Noserator. However, this "cure" proves to be temporary, and by the end of the episode his nose is all stuffed-up again.
In the Rugrats films
- The Rugrats Movie
Chuckie is in a truck with the other Rugrats and he keeps bouncing in the air back and forth and he says "I don't know if I should throw up or throw down". Tommy doesn’t save him when he falls into the water because Tommy had to get Dil because Dil was only a baby and Tommy didn't want Dil to drown. He gets his glasses stolen by the monkeys and he accidentally steps on them a little bit when he finds them.
- Rugrats in Paris: The Movie
Chuckie is the main character with a bigger role and hero; something that had rarely happened before in the series. His heroism is shown when he leads the babies on the giant Reptar to the church to stop Coco from marrying his father, Chas. He carries a teddy bear named Wawa that his late mother made him. Wawa is Chuckie's security blanket, attachment or travel companion, like Angelica and her doll, Cynthia.
In All Grown Up!
Since he got older, Chuckie has been wearing braces for his teeth. He still considers Tommy his best friend, but he is not as close to his dad as he used to be. Notable storylines for Chuckie have included his crush on Nicole Boscarelli, dropped after the first season; partnering with Angelica on a social-studies project; entering the safety commissioner election against an imaginary friend, inexplicably dropped without even mentioning the final result; and dragging in what looked like a trashed Christmas tree.