|Appearance:||Lab Coat, Pink Dress|
Dee Dee is Dexter's extremely ditzy, naive, simple-minded older sister. She is in the 6th Grade and loves ballet, dolls, ponies, unicorns and (most of all, it seems) messing around in Dexter's laboratory, and generally depicts all the stereotypes concerning young girls. She is quite similar to the Powerpuff Girls character Bubbles, both in appearance and personality. She is two to three times taller than Dexter and has peculiar body proportions; a minuscule torso with a large head and gangly limbs, similar to a ballerina's. To complete the ballet look, she wears a small pink tutu and ballet shoes, which usually create a "squishy" noise while walking. Dexter once compared her to a stick and subsequently threw her to entertain a dog. She occasionally reveals a deep depth of hidden knowledge being able to beat Dexter on a test and therefore driving him insane, and once functioned as a guru for Dexter, teaching him "The Way of the Dee Dee". Although she seems to be extremely moronic, her social skills far exceed Dexter's, as she is quite popular at their local school, while he is shunned except for his other equally geeky associates. Her best friends in the series are Mee Mee and Lee Lee, two girls that share her interests, even though they are noticeably different in appearance (Mee Mee is African-American with afro puffs, and Lee Lee is Asian.) Her catch-phrase is "Ooooooo. What does this button do?". She wears her full length of hair down on rare occasions, mostly when sleeping. She also has a multitude of stuffed animals and she has a four poster bed (although she has been seen to have a bed similar to Dexter's in a few episodes). It was revealed in the episode "A Hard Day's Day" that Dee Dee is a Cancer. Originally voiced by Allison Moore, the role was assumed by Kathryn Cressida after the first season. Moore reprised the role in the third season, with Cressida taking it back for the show's final season. Dee Dee bugs Dexter so much because she wants to spend time with her little brother and because she thinks that his secret lab is cool. Dexter considers his sister Dee Dee to be stupid, clumsy, and inferior to him, most ironically when Dee Dee tricks him with urban myths and false information about certain diseases. Dee Dee also enjoys succeeding where Dexter fails, whether its beating him at an unnecessary game or skill, or entering a contest just because Dexter is in it and winning. On rare occasions Dee Dee and Dexter work together, he also rarely shows affection to her. While Dexter seems harsh to Dee Dee his feelings are occasionally quite justified as Dee Dee continually destroys parts of his lab, sometimes blowing up the whole lab which forces Dexter to have to rebuild everything countless times.
Dee Dee wears a pink dress and ballet slippers , blue colored eyes, blonde hair and pigtails.