Roosevelt took office as vice president in March 1901 and assumed the presidency at age 42 after McKinley was assassinated the following September. At age nine, he recorded his observation of insects in a paper entitled 'The Natural History of Insects'.Roosevelt's father significantly influenced him. His father was a prominent leader in New York's cultural affairs; he helped to found the Metropolitan Museum of Art, and had been especially active in mobilizing support for the Union during the Civil War, even though his in-laws included Confederate leaders. A 6-year-old Roosevelt witnessed the funeral procession of Abraham Lincoln from his grandfather's mansion in Union Square, New York City where he was photographed in the window along with his brother Elliott, as confirmed by wife Edith who was also present.