Did you catch this in Scream? Sam's struggle to embrace the reality of who her father really is is one of the key aspects of her personality. She is seen throughout the film attempting to treat her hallucinations of her father with antipsychotic medication, but she is unsuccessful since Skeet Ulrich reprises his role as Billy. Sam's attire in the hospital is a simple white t-shirt, a homage to Billy Loomis' classic outfit from the first movie, which she sees him wearing in her hallucinations. She wipes the blood off her knife in a way that is undeniably Ghostface-like when she violently stabs Ritchie to death at the conclusion of the movie. Apples don't generally fall too far from the tree.