Jessie Harlan Lincoln (1875 - 1948) was the second daughter of Robert Todd Lincoln, the granddaughter of Abraham Lincoln, and the mother of Mary Lincoln Beckwith and Robert Todd Lincoln Beckwith, the last undisputed Lincoln descendant
Mary Lincoln "Peggy" Beckwith (1898 - 1975) was a prominent descendant of Abraham Lincoln. She was one of the last two descendants (great grandchildren) of Abraham Lincoln, along with her brother Robert Todd Lincoln Beckwith
Robert Todd Lincoln Beckwith, President Lincoln's great grandson and last descendant, married three times and lived to be 84 years of age. As was the case with Lincoln's two other great grandchildren, he did not have any children thus ending the Lincoln line of descendants.