Michael, I ran into the same problem you did a few years ago. Lyman Alexander Walkup is NOT the son of Arthur Walkup. I have seen this same mistake published in the book "Walkups - An American Family for 300 Years."
Lyman and his wife Eliza had 13 children. Their 7th child was my great grandfather John Malcolm.His 11th child was Charles Edward. Lyman's parents were Joseph Walkup and Nancy Ann Price.
You can email me back if you like at firstname.lastname@example.org