There is a guest account on the Navarres.. Username: guest:Password:OFGPguest
In John V. Beck's book Elisha S. and Lavina (Locke) Andrus their ancestors and descendants also talks about it a little bit on page 17.. apparently in Robert Porter's family tree, they are brothers, but I think that is only assumption.
In my personal research, I researched the wrong John Andrews(181), and traced his ancestors, and they reconnect at Thomas Andrews. So that would mean the two John Andrews (181 and 153) are third cousins twice removed.
I think it's crazy that you just want to leave it without a father, as a fellow descendant, I would love to connect him to Thomas. If everyone believes that Francis and John are brothers, then it must be true. Even if, we can mention it on the profiles, that there is no concrete evidence of it, but it most likely is true.
EDIT: Sorry! I was meaning to refer to Abraham when I said "his". Thomas is who I think is John and Francis's father.