The Marcus Family are the antagonists of the second Goosebumps Most Wanted: Special Edition book, The 12 Screams of Christmas. They consist of Aaron, Peg, and their children Abe, Ned, and Flora. Abe narrates the prologue of the book.
In December of 1882, the family had moved from a small cottage to a large house, which were they excited to do. While the children were exploring their backyard, Flora accidentally fell down the fell. They were unable to get her out, and soon she went silent. The family died sometime later and from then on they were haunting the house.
Many years later, a class trip held by drama teacher Mr. Piccolo, who claimed to be the a descendant of the family, went to the Marcus house to rehearse a Christmas play that was inspired by the Marcus' story. Kate Welles, a girl in the class, had the power to see ghosts and the twins Ned and Marcus took advantage of this when they saw her to have her replace Flora. They wanted her so that they can finally have a real family for Christmas.
They held her captive in the attic and forced her to partake in their Christmas traditions, such as making her sit on the lap of skeleton that was dressed as Father Christmas. They got upset when Kate refused to do so and they tried to get rid of her. However, she managed to rescue Flora by screaming "Come up! twelve times. She did this with the help of Courtney Smith, who Flora thanked, causing her to run screaming.
Kate went home, only for Flora to follow her back. She decided to stay with Kate, as she was upset with her family for leaving her in the well for one hundred years.
Flora is a spoiled girl but her family still missed her dearly after she fell down the well, to the point that they tried to recreate their old family Christmases with Kate. Abe is the more serious of the twins, while Ned likes to play pranks.
Aaron is desctibed as lanky and bone thing, with scraggly brown hair parted in the middle and down the sides of his cheeks. Peg is plump and round faced, with dark ringlets of hair falling down to her shoulders. Ned, Abe and Flora all have dark wavy hair, but Flora's is rarely seen because she is always wearing a red cap.