Thomas "Tad" Lincoln III - Fourth and youngest son of Abraham and Mary Lincoln. The nickname "Tad" was given to him by his father, who found him "as wiggly as a tadpole" when he was a baby. He had free run of the White House, and there are stories of him interrupting Presidential meetings, collecting animals, and charging visitors to see his father. He died at the age of 18 on July 15, 1871, in Chicago.
12. Zachary Taylor (November 24, 1784 – July 9, 1850) was the 12th U.S. president (1849–1850) & an American military leader. Initially uninterested in politics, he nonetheless ran as a Whig in the 1848 presidential election, defeating Lewis Cass. Taylor was the last President to hold slaves while in office, and the second and also last Whig to win a presidential election. He was the second president to die in office, following William Henry Harrison, who had died 9 years earlier.