Is it normal to sleep with my sister ?

My sister is scared to sleep alone tonight because she had a bad dream. She dreamed she and her dad and his friend had to drive out to Oklahoma during a really bad storm that formed a tornado luckily they got out in time but the news said they didn't she's scared she can't go back to sleep she wants me to sleep with her. She said her stomach is hurting. I put the tv on for her she still doesn't want to sleep. I told her that isn't possible there is no way our dad could drive from Ohio to Oklahoma in one day. He wouldn't need to go there anyway even if he did he probably wouldn't take her and he probably wouldn't go during tornado season. She's really scared she wants me to sleep with her. How can I calm her down ? Is it normal to sleep with her ?