Descendants of US presidents reflect on their legacies as America turns 250

As the nation prepares to mark the 250th anniversary of the U.S. signing the Declaration of Independence, ABC News tracked down the descendants of former U.S. presidents.

Those presidential relatives shared stories about their ancestors and their lasting impacts on the country.

ABC is marking America's 250th anniversary with 24 hours of programming called "Disney Celebrates America."

The multi-platform broadcast, led by ABC News "World News Tonight" anchor David Muir, will feature coverage across all 50 states, beginning 10 p.m. ET on July 3 and running through July 4.

Thomas R. Washington is the fifth nephew of former President George Washington. Washington was one of the nation's Founding Fathers and its first president, serving from 1789 to 1797.  Thomas wants to live up to his reputation.

"I tend to try to be honest in my dealings with people. I want to be trustworthy. I think those were two features that George Washington had in abundance. I try to be intellectual, I try to learn, I tried to treat people right," he told ABC News. "And I see some of those same qualities in other family members from the Washington family, and perhaps it's passed down."

Ben Adams is the third great-grandson of former President John Quincy Adams, who served as the sixth president of the U.S. from 1825 to 1829.

"I suppose one of his most incredible accomplishments was, after having had a long career as a diplomat and as president of the United States and secretary of state, he actually chose to return to Congress after he was president. He was the only president who actually did so," Ben Adams said.

He also highlighted one of his relative's apparent methods of relaxation.

"John Quincy Adams was famous for skinny dipping in the Potomac River, which was a practice he apparently undertook almost every day, at least when the weather was warm," he said.

Gary Mattingly is the great grandnephew of former President Zachary Taylor, who served as the 12th U.S. president from 1849 until his death in 1850.

"My uncle's greatest accomplishment was being the first president to hold office who had no political background at all. He was a soldier first," Mattingly said.

He also highlighted "a little-known fact" about his ancestor.

"His presidency was cut short 18 months in, and there were rumors even back then of assassination, and he would be exhumed 150 years later to test that theory, and while we don't think it's true, they were never able to conclusively disprove it," Mattingly said.

Catherine West is the great-great niece of former President James Buchanan, who served as the 15th president from 1857 to 1861. She noted that Buchanan is known for being "the only lifelong bachelor" to hold the office.

West also highlighted his remarkably long service to the country "for someone who was expelled from college for disorderly conduct, namely, drinking and dancing on the table at local taverns, disturbing the peace, acts of vandalism around town, throwing food in the school's cafeteria, and insubordination."

Tim York is the second cousin to former President Abraham Lincoln, who served as the 16th president from 1861 until his assassination in 1865. The Civil War raged during his time in office.

"My second cousin's greatest accomplishment was obviously bringing the country together, uniting it through a bloody war, but it was something that had to be done and he accomplished that and definitely the Emancipation Proclamation Act, making it possible for all men to be free," York said.

Ulysses Grant Dietz is the youngest great-great-grandchild of former president Ulysses S. Grant, who served as the 18th president from 1869 to 1877. Grant Dietz highlighted his ancestor's public feat, which he accomplished as commanding general of the Union Army before he became president.

"A lot of people would say his greatest accomplishment was defeating Robert E. Lee, ending the Civil War, and ending slavery in America," he said.

Grant Dietz also noted a more personal act after that came after Grant's time in office.

"From my personal point of view, his greatest achievement was writing his own memoirs in the space of less than a year as he was dying of cancer and not only creating the greatest military memoir in the history of the country, or maybe in the history of the world, but also saving his family from poverty," he said.

Melanie Eisenhower is the great granddaughter of former President Dwight Eisenhower, who served as the 34th president from 1953 to 1961. She noted that his "greatest accomplishment" came before he was president, when he was a general in World War II.

"When he decided to invade Normandy on D-Day, that was perhaps the most important moment of his life," she said. "And the success of that mission really spurred on other successes in his life, like victory in Europe and also his election to presidency."

Melanie Eisenhower also highlighted his sporting career.

"A little-known fact about my great-grandfather Eisenhower is that he was a professional baseball player for two years before he went to West Point," she said. "So this was not known and he was never public about it because if West Point had known then he would not have been able to participate in athletics at West Point and so this was a secret and he went by an alias."

James Carter IV, the grandson of former President Jimmy Carter, spoke about the 39th president's foreign policy success when he held the office from 1977 and 1981.

"His great accomplishment was the Camp David Peace Accords between Israel and Egypt. And one story you may not have heard about him is that those peace talks almost failed until he presented the two principals with pictures of their own grandkids to remind them what was at stake," James Carter IV said.