"We've got to find out who that Sinister Pumpkin is! Jinkies! A clue!"
"The Sinister Pumkin is no other than my little sister!"
"And I would have gotten away with it too, if it were not for my meddling older sister!"
One sweater, knit up in short order using Very Big Yarn (Lion Brand Thick and Quick in Pumpkin) and Very Big Needles (15mm!!!); the kids went shopping for the rest.