Hey Cousin! I figured it out. I got confirmation just two weeks ago when I went to visit my Uncle and got a book from him called Men of the Mark from 1776-1876. It's a history of military men in the Penn. Area near where the Agnews came. On the inside is an inscription by John R. Agnew to his nephew Nathaniel Sample Agnew requesting that the book be passed on to his son John Patterson Agnew, his (John's) namesake.
Nathaniel Sample Agnew (1845) was John Patterson Agnew's (1879) Father. Nathaniel married Mary E. Ritchie in 1867.
Nathaniel's father was David Agnew (1811) and his mother was Rebecca C. Sample.
David's father was James Agnew (1769) and his mother was ELizabeth Finley. James married again after Elizabeth passed away to Rebecca Patterson (found the link). Looks like Elizabeth died when the kids were still young.
James' father was James Scott Agnew (1742) and his mother was Mary Ramsey.
James Scott's father was James Agnew (1711) and his mother was Rebecca Scott
James' father was James Agnew (1645) and his mother was Eleanor Jamieson (is her first name Helena?)
James' father was Alexander Agnew (does anyone know his wifes name?)
Alexander's father was Patrick Agnew and his mother was Margaret Kennedy.
So apparently we are cousins somehow. So again I say hey cousin. If any of this looks wrong let me know.