what did Aunt Polly find that resolved Tom of all his lies?

Tom says that he had dreamed about Aunt Polly. Out of curiosity, Aunt Polly inquires Tom about his dream. Tom recalls the incidents of Wednesday night, but implies that he dreamt the entire account. He recalls the entire family, including Mrs. Harper, sitting and crying by the door. "I took and wrote on a piece of sycamore bark, ŒWe ain't dead ­ we are only off being pirates,' and put it on the table by the candleŠ I thought I went and leaned over and kissed you on the lips." Polly, convinced that Tom had prophesied the account and that an angel must have been present, rewards Tom with an apple and kisses before sending him off to school.