On many of the pedigrees posted online, Mercy's maiden name is given as DELOP or DUNLOP. I don't know where this name comes from - I've tried contacting people about it, but of the few who have responded, they said they just got it from others online. However, given the close association of the SKINNER & KEENY/KENNEY/KINNE/KINNEY/etc. families, emigrating from CT to NY & PA together in the late 1700s, I think Mercy's surname as KINNEY/etc. is not an unreasonable theory.
Any info will be welcome, even if it's DELOP/DUNLOP info.