Chapter 8: who put the blanket around Scout?

In Chapter Eight, Atticus notices that Scout has a blanket wrapped around her shoulders and scolds her for straying from the one spot he told her to stay in. Scout explains that neither she nor Jem left the Radley yard and that they don't know where the blanket came from. They realize that Boo Radley must have slipped the blanket over Scout while she and Jem were engrossed by the fire. Mr. Radley, his brother, had been busy helping everyone else at Miss Maudie's house, so Boo is the only person that could have given Scout the blanket. Scout is amazed that she was so close to Boo and didn't even know it.