Andrew Jackson Houston made history on June 2, 1941, when he became the oldest man ever to become a freshman United States senator. When Andrew was born, eighty-six years earlier, his father—Sam Houston—held the Texas U.S. Senate seat that his son would later occupy.

As the son of Sam Houston, Andrew had enjoyed celebrity status throughout Texas in the late nineteenth and early twentieth centuries. He attended West Point, joined a law firm, rose up through the ranks in the Texas National Guard, organized a company of "Rough Riders" for Teddy Roosevelt during the Spanish-American War, and served as a U.S. marshal. From 1924 until 1941, he superintended the San Jacinto Battlefield where his father in 1836 had won his greatest military victory.

In the spring of 1941, on the 105th anniversary of the Battle of San Jacinto, the governor of Texas visited Houston at his ranch. After a few moments of casual conversation, Governor W. Lee O'Daniel told Houston that he would like to appoint him to a U.S. Senate seat that had recently fallen vacant on the death of an incumbent.

O'Daniel made the offer as part of his strategy to win the seat for himself in an upcoming special election. Rather than choosing an active political figure, who might benefit from the visibility of an interim appointment in a primary election that would eventually attract twenty-six candidates, O'Daniel chose a non-threatening political icon to keep the seat warm until the election.

Defying the wishes of his family and physician, the frail Houston agreed and made the arduous journey by rail to Washington. On June 2, 1941, in the Senate chamber crowded with those wishing to glimpse a bit of history in the making, Houston took his oath from Vice President Henry Wallace. Deteriorating health, however, limited his actual participation in Senate proceedings to four days. He attended one committee meeting and introduced two bills, both related to preserving the memory of his father's contributions. Then he entered Johns Hopkins University Hospital, where, on June 26, he died from complications of surgery

Thus ended the longest father-son life span in Senate history. The father was born in the first administration of President George Washington; the son died in the third term of Franklin Roosevelt.

Two days later, Governor O'Daniel easily won election to the balance of the vacant term.