It is very easy to confuse information on father and son with the same names. It could be the father Reuben Parker did not serve in the American Revolution, but had Patriotic Service. If the son Reuben was born in 1734, then the father was born in the early 1700's and would have been too old. He could have patriotic service, which includes: Oath of Fidelity and Support, Oath of Allegiance, rendered material aid, such as furnishing supplies, members of the Boston Tea Party, Members of Continental Congresses, State Conventions and assemblies......
I wish you luck,
Barb