Quick recap
Bean's grandchildren, the Leguminids, get a message that sends them to Lusitania. There, the Lusitanians are studying the planet Descoladora, source of the Descolada virus's genome. Thulium, one of the grandchildren, learns the Formics survived and bonds with the Hive Queen. Peter Wiggin II and Si Wang-mu make first contact with intelligent birds on the planet Nest. Her cousin Sprout meets the Engineers and the Folk, who expose Thulium to a bioweapon; the Queen saves her. When many of Nest's birds suddenly die, Lusitania organizes moving them to other worlds. Research shows the Descolada turned lethal because of cosmic radiation, and the method to neutralize it is published. Peter and Wang-mu have a child.
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