What was the sequel to Tom Sawyer?

If you're discussing the original book by Mark Twain, the follow-up book was The Adventures of Huckleberry Finn by the same author. Interestingly, there is now a new sequel to both books by an author named Andrew Joyce titled, "Redemption, The Further Adventures Of Huck & Tom". It's an Amazon e-book and I understand it's getting good reviews and is selling quite well.