Who is the First president to be widowed and remarried?

After the death of William Henry Harrison, John Tyler became the 10th President of the United States of America, and he was the first president to be widowed and remarried. Tyler's first wife was Letitia Christian Tyler, whom he had 8 children with, and she died in the White House in September 1842. Tyler then married a second time. Tyler's second wife was Julia Gardiner Tyler, with whom he had 7 children with .