Eleven-year-old Summer and her older brother Rosco each have a "silent thunder, " a desire that rumbles deep within them, refusing to be ignored. Summer longs to learn to read. Rosco is burning to fight for his Country and his freedom. But Rosco and Summer are slaves on Gideon Parnell's plantation in the year 1862, and for slaves, these desires are illegal and dangerous.Despite the danger and their mama's terrible fear of being sold off, Summer and Rosco are determined to fulfill their dreams. In stolen moments, Rosco teaches Summer all he has learned from eavesdropping on young master Lowell's lessons. In the meantime, Rosco secretly plans his own escape to the North, to join the Union forces. But when Gideon Parnell unexpectedly falls ill and the plantation is taken over by Parnell's cruel brother-in-law, Rosco's decision becomes more complicated. How can he leave his family now? And Summer, struggling to understand her mama's perplexing actions, discovers that Mama has a silent thunder of her own -- and secrets Summer never dreamed of.Through the voices of Rosco and Summer, this wrenching yet hopeful novel celebrates the triu