Alfonsa CAHOON m Charles SAULSBURY in Delaware

I am looking for information on Alfonsa B CAHOON and Charles SAULSBURY both born in Delaware.

I am related through their daughter, Rebecca S. Saulsbury, who was
b. August 24, 1863 in Delaware
m. September 13, 1881 in Denton, MD, to Charles Bateson
d. September 4, 1926 in Philadelphia, PA

According to the 1880 census, there is an Alfred Saulsbury(female) b. 1850 and her apparent daughter, Rebecca J, b. 1862 in Mispillion Hundred.This is the only clue I have so far.

I would appreciate any information.