Aaron Burr became a U.S. senator in 1791, taking over the New York seat once held by Philip Schuyler, father-in-law to his political adversary Alexander Hamilton (via United States Senate). Theodosia's health, which had already been poor, soon took a turn for the worse, and her husband became very concerned. He often received reports of Theodosia's health from their daughter while he was away.
Burr frequently wrote to their daughter, whom he nicknamed Theo, looking for updates on Theodosia's condition. "I'm extremely impatient for your farther account of mamma's health. . . . Your letter was written a week ago, which since I have no account" (via "The Heartbreak of Aaron Burr"). Theodosia was given all sorts of medications from the time, such as taking laudanum twice a day. Laudanum is a painkiller solution derived from opium (via Britannica). She was thought to have cancer, and none of the treatments had any effect on the progression of the disease.
Theodosia died in 1748 (via Aaron Burr Association). After Theodosia's death, Burr wrote "The mother of my Theo was the best woman and finest lady I have ever known." She reportedly was laid to rest in St. John's Burying Ground in New York City, which later became known as James J. Walker Park (via Find a Grave).
