No, Parable of the Sower is not a sequel. It is a stand-alone novel written by Octavia E. Butler. While it is set in the same future-dystopian world as her previous book, Dawn, there is no direct narrative connection between the two stories.
Parable of the Sower provides an intriguing exploration of the power of hope, community, and possibility through the protagonist Lauren Olamina's journey. It follows her brave quest for a better future, as she and her small group of followers attempt to build a more equitable society, free from the societal inequality that plagued her hometown of Robledo.
The novel paints a vivid picture of a future America, ravaged by environmental disasters, economic instability, and racism. Butler creates a powerful narrative rich with gripping characters and ideas, one that merits consideration as a work of classic dystopian literature alongside books like George Orwell's 1984 and Aldous Huxley's Brave New World.
In short, although Parable of the Sower is set in the same universe as her book Dawn, it is not a sequel, and is a definite must-read for all fans of dystopian fiction.