Freaky sleepwalking kid

When my eldest son was way younger he had a sleep over at our house with a bunch of other friends from school. Well he comes up to me the next day after he gets back from school and tells me one of the girls was staring and smiling at him in the middle of the night. My son is a sensitive young man and this scared the crap out of him, but he just rolled over and was able to ignore her he said. I didn't worry about it but he's never come to me with anything like that before. So on day 2 of this week long slumber party birthday bonanza he come to me before they got on the school bus and said the same girl was making the same face and smile last night and was playing with someones Vans or something. At that point I'm thinking he's having nightmares because this girl is super sweet and chill. I mean she was 9 and still carried a blanket in her back pack. So I tell him to go to school and they all did and 3rd night nothing happens to my knowledge. 4th night tho I wake up to tapping sound and, gurl, this kid is in my bedroom in the middle of the night smiling and looking out the window like a mini psychopath. She's jus standing there, poking the damn window and I'm freaking out so I woke up my bf. He sees her and is freaked out too so we call her name but she doesn't say anything or look at us but she stops messing with the window. We get up and ask her if she's ok and stuff but she still didn't move except her lips. They went from curling out to curling in while she was smiling. She's creeping us out but we can tell she's got to be sleep walking. We usher her back to the livingroom to the couch and she's looking up staring at my bfs face the whole time. I admit I put her in the living room because I didn't want her back in my sons room after that. Well she layed down and went to real sleep so we talked about calling her mom but it was the middle of the night so we just texted her and went back to bed with the door closed this time. Her mom texted me back in the morning and said she didn't know she sleep walked or anything. We decided to cut the sleep over week short and had them all go to their normal bus stops so they could all go home that day. Creepiest thing I've EVER been through!!!