Our 11-year-old son is refusing to go to bed in his own room. Until recently, I had been allowing him to sleep with his six year-old sister, but my husband didn't want to let him do that anymore. I thought he would just grow out of it, but, I told him yesterday that he had to go to sleep in his own room. The first night he did it. Last night he refused and said he was scared. I told him he could grab a blanket and sleep on our (very hard terrazo) floor, which he did. How can we get him to go to bed in his own room? He says he's scared.