in the
Amazon Basin. One of Theodore Roosevelt's most popular books,
Through the Brazilian Wilderness, recounted the expedition into the
Amazon Basin Brazilian jungle in 1913–14. The father and son went on what would become known as the
Roosevelt-Rondon Scientific Expedition, exploring the Brazilian jungle with explorer Colonel
Cândido Rondon. During this expedition, they explored the
River of Doubt, later renamed
Rio Roosevelt in honor of the President, as well as a branch of that river named the Rio Kermit in his honor. The source of the river had been discovered by Rondon earlier, but it had never been fully explored or mapped. At the time of the expedition, Kermit Roosevelt was newly engaged to Belle Wyatt Willard, daughter of the U.S. ambassador to Spain. His mother Edith, however, was concerned about her husband Theodore's health and the difficulties of a new expedition, and asked Kermit to accompany his father. He did so, reluctantly delaying his marriage. The scope of the expedition expanded beyond the original plans, leaving the participants inadequately prepared for a trip tracing the River of Doubt from its source through hundreds of kilometers of uncharted
rainforest. The climate and terrain, inadequate gear and food, and two deaths (one drowning, the other murder) turned a scientific expedition into an ordeal. Roosevelt's father contracted
malaria and a serious infection resulting from a minor leg wound, weakening him to the point that he considered taking a fatal dose of morphine rather than being a burden to his companions. The younger Roosevelt told his father that he was bringing him back literally "dead or alive": so if he died, he would be an even bigger burden on the expedition. Although Kermit contracted malaria as well, he downplayed his sickness to save
quinine for TR, nearly dying himself before the physician insisted on giving him the medication by injection. Kermit Roosevelt's determination and his rope- and canoe-handling skills were instrumental in saving his father's life, though TR would in later life be plagued by flareups of malaria and inflammation so severe that they required hospitalization. Although Kermit and TR faced skepticism about their claims of navigating a completely uncharted river over 1000 km long, they eventually silenced their critics through TR's oratory and his popular book,
Through the Brazilian Wilderness. The 1913–14 expedition was later recounted in the book
The River of Doubt by
Candice Millard (Doubleday 2005). ==Marriage and children==