Is there a sequel to The Giver by Lois Lowry?

Gathering Blue and Messenger, along with The Giver, form a loose trilogy. In Gathering Blue, none of the characters from The Giver appear, but Jonas (called Leader) and Gabriel (who is mentioned by name) are in Messenger, which takes place 8 years after The Giver. The characters from Gathering Blue also play an important role in Messenger, so all the books are connected.