Other mistake: When Snoopy starts sneaking through the pumpkin patch, Sally is standing with her arms crossed and Sally's hand is painted blue while talking to Linus. (00:20:35)
Other mistake: When the kids leave Linus standing alone in the pumpkin patch, Sally decides to rush back to Linus, and when Linus explains that she'll see the Great Pumpkin with her own eyes, Sally's left arm is blue, the same color as her dress, then instantly changes to the normal flesh color within the same shot. (00:11:20)
Other mistake: At the very beginning, just after Lucy and Linus exit the house, walk down the house steps and make it to the grass, the house steps do a little "jump". (00:00:20)
Other mistake: When Lucy asks for an extra piece of candy for her brother during the Trick or Treat scene, her right hand has five fingers when she holds it up, but her left hand only has four fingers.
Other mistake: There is very little drawn correctly about the neighborhood as Lucy and Linus are walking through it in the beginning. There are houses dotted throughout, but all directly on the grass. There's no streets, no sidewalks, no driveways, and most don't even have a garage. However there is one random electric telephone pole they pass.
Answer: From what I've seen, usually Sally is often annoying Linus with her flirting when he has nothing in common with her, or he's just trying to do something to help her and she tries to make it into more. Here, Sally's comments make Linus think she believes in the Great Pumpkin too, or is at least interested in hearing more about it. It's more that he's excited she likes the same thing as he does. Later in the pumpkin patch, he's happy she's there because he wants to share the experience with someone, not because he has any feeling towards Sally.
Bishop73