From "The Daniel Dennistons of Beverley Manor and Descendants", by John B. Robb:
xiii. CATHERINE DENNISON. Catherine Dennison was born 1770, probably late in the year, given that she was apparently in her 50s when the 1830 USCensus was taken.[72] Evidently she never married, since she was still Catherine Denison at age 80. She died, probably in Fayette Co KY after 7Aug1850, when she was living with her niece by her sister Isabella Atchison, Rebecca Pettit.
http://www.johnbrobb.com/Content/DennisonReport.pdf