Sophie Piper, portrayed by Emily Roeske, is a character who appears throughout the Halloweentown film series.
Sophie is the youngest daughter of Gwen and William Piper, the granddaughter of Aggie Cromwell, and the younger sister of Marnie and Dylan Piper. Like Marnie, she is also a witch. She can cast simple spells that she learns from her sister and grandmother. Unlike her older sister Marnie, the more advanced witch, Sophie appears to have a stronger hold on her precognitive powers. She can sense the presence of "bad things" to which she would always reply "Somebody's coming". She also has proven to have a knack for remembering spells, something Marnie continues to have trouble with. She also is very resilient and quick at problem-solving. Sophie, like her sister and grandmother, has shown efficiency in conjuring. Along with her precognitive abilities, it appears that Sophie is telekinetic.
In Halloweentown, Sophie is about 7 years old and can control her powers better than her sister can, as her grandmother states it only takes will and imagination for the magic to work.
In Halloweentown II: Kalabar's Revenge, Sophie can sense Kal's presence, which her grandmother, mother, sister and brother can't (although Gwen later can and Dylan indicates he senses something is wrong), but has a hard time controlling her flying abilities because Aggie hadn't taught her how to fly yet.
In Halloweentown High, Sophie appears briefly and doesn't do magic at all.
Sophie does not appear in Return to Halloweentown, but it is mentioned that she has started her witches training under her grandmother, Aggie.