South Park. She is Stan's older sister, and is named for Trey Parker's older sister. Shelly has been voiced by Mary Kay Bergman, Mona Marshall, and then Eliza Schneider. She is now voiced by April Stewart. She usually calls Stan and his friends "Turds".
Shelly Marsh wears a grayish-white shirt and pink jeans. She has long, brown hair and bangs. She has bad dental problems and has to wear orthodontic head gear, giving her a very unappealing appearance. Because of that, she is usually scowling or frowning. She has a distinct adenoidal, slurred voice, where she breathes heavily through her mouth and nose, and lisps. On some occasions, she has been seen with her pajamas on; her pajama shirt is pink. For special occasions she wears a pink dress.
Shelly Marsh is filled with a lot of anger and hatred, mostly caused by the head gear she has to wear. Her favorite way to vent this anger and hate is to beat up on her younger brother, Stan. The anger also comes from the fact she is not very good-looking, with or without the head gear, and nobody likes her at school because of that. This issue is explored in the episode "Cat Orgy", where she confesses this to Cartman. In addition to revealing a nice side during "Cat Orgy", Shelly has also been found to show compassion for her little brother Stan (usually after he plays the Brother-Sister-Family Card) when all other choices have been exhausted. A perfect example of this is the episode "Preschool" where Stan and the others are threatened to be killed by Trent Boyett, Shelly vows to protect her little brother because killing him is her job. She insists however that Stan come clean about the lies that made Trent want to kill him in the first place showing that Shelly also cares about the way Stan is growing up and tries to teach him how to be a responsible person. Shelly has also been shown to be exceptionally strong, even being able to pick up an entire piano in Mr. Hankey's Christmas Classics and drop it on Stan and Kyle, and when the boys turned to her as a last resort when the sixth graders couldn't stop Trent Boyett, implying that Shelly alone is stronger then all of the sixth graders combined.
Shelly loves watching television. Her favorite shows include "Buffy the Vampire Slayer" and "Friends." She is also a fan of Russell Crowe, but all these things fall short of her favorite pastime: making Stan suffer. She also enjoys listening to Britney Spears records. In "Over Logging", there were posters of horses in the back of her room. This could mean she likes horses. Another poster of Sadie Dakota (a parody of Hannah Montana) can also be seen.
It is suggested that Shelly was not always angry, and that she only gained a temper after she got braces. The braces gave her a dowdy appearance and gave her low self esteem, causing her to pick on her brother Stan. No one believed Shelly was beating up Stan, due to the fact when their parents were around she would act sweet and innocent (although Shelly whacked Stan a few times in front of her parents and received no reprimands). After the house was destroyed after a fight between the two, Randy and Sharon were planning on sending Stan to military camp. It was then that Shelly confessed she was beating him up, and it had been her fault.
No one liked Shelly at school, which led her into a relationship with a twenty-two year old, Skylar, who did like her. He broke up with her after she wouldn't have sex him. This made her depressed and it took Eric Cartman, the boy she had been baby-sitting when Skylar broke up with her, to make her realize that she did not need Skylar and that he was a jerk. The two had been enemies, but soon became friends after getting revenge on Skylar.
In the season twelve episode "Over Logging", Shelly had a new boyfriend over the internet for some time. She believes that the emotions between herself and Amir are real. At the end of the episode, it is revealed that he does care for her, as he also traveled to California so that he and she could resume chatting online. There, they also end up meeting in person, and promise to e-mail each other that night.
- Her name is alternatively spelled on the main site as both "Shelley" and "Shelly".
- She is named after Trey Parker's sister Shelly, but interestingly, Shelly can be used as short for Rachel, which is the name of Matt Stone's sister.
He is Shelly's younger brother. She used to beat him up much of the time, but was not seen doing so for a time. She did start punching him repeatedly in "Over Logging", however, when she thought of how her online boyfriend might worry for her if they could no longer e-mail each other. To date, this episode is the only instance in which her violence towards Stan is noticed by their parents, as Randy then runs over and tells Shelly to calm down. Shelly and Stan may have resolved their sibling rivalry, as Shelly has not shown any violence towards Stan since "Over Logging".
She is Shelly's mother. Of all the grownups in the family, Sharon seems closest to Shelly.
Randy is Shelly's father. He is usually seen interacting with Stan, but he and Shelly have spoken to each other several times. She was frustrated by Randy recording ridiculously everyday family antics, saying "Turn it off, Dad!"
He is Shelly's paternal grandfather. She seems to love him a lot, because when she thought Stan was trying to kill him, she grew even angrier than usual at him.
He is Shelly's uncle. Not much interaction happens between them.
She was Shelly's maternal great-aunt. Aunt Flo gave Shelly a television/CD player/surround sound home theater for Halloween, before she was killed by the evil goldfish she gave Stan.
Roy is Shelly's step dad. After Sharon divorces Randy in "Clubhouses", she stays with Roy. They stayed together until Sharon dared Randy to have sex with her and they make up.