It appears Abigail was married to Joseph "C" Hopkins on his tombstone. It is actually Joseph "G" (Gilbert) Hopkins. The "G" in Abigail also looks like a "C", it is just a typeface misinterpretaion which has often been mistranscribed.
Other child of Abigail's and Joseph's is:
Albert Cole Hopkins - b. 1837; d. 1909 Lock Haven, Clinton Co, PA