Amazing, but there is still a living grandson of President John Tyler, who was born in 1790 and served his country from 1841-1845. The grandson explains how this happened:
Both my grandfather — the president — and my father, were married twice. And they had children by their first wives. And their first wives died, and they married again and had more children. And my father was 75 when I was born, his father was 63 when he was born. John Tyler had fifteen children — eight by his first wife, seven by his second wife — so it does get very confusing.
It’s amazing to think about how relatively young the American Republic really is.