I'd been assuming -- for lack of information and based on some decades-old speculation -- that Francis Nelson LaPore was the brother of my 3GRGR, Julien. Shortly after the "Denis" discovery that was the breakthrough to getting his ancestry, I began to doubt whether Francis Nelson was actually a brother. There didn't seem to be any record of him as a son born to Charles Denis and Marie Guenet.
Recently, a man contacted me about "Joseph LaPorte" -- another person speculated to be a brother of 3GRGR -- but again another who I'd suspected not to be. He is the Joseph married to Nancy Beagle.
In poking around recently regarding Joseph, I also started to look at the "La France" collection of records for Jean-Baptiste LaPorte and Marie-Agathe Masse. They spent a good deal of time in Marieville, Quebec, Canada, and so I started plodding through the index records from there.
What I found is interesting. There was a "Francoise" born of JB and Marie-Agathe in 1814. I asterisked this fact in my mind as a possible "Francis Nelson" as Francoise anglicized is Francis. Mostly, though, I was focused on Joseph and also poking around the family of another Julien -- this one a sibling of this Jean Baptiste that I've been looking at. Seeing that this Joseph was born in 1816, I thought there was a good chance he could be the Joseph married to Nancy Beagle, who I currently had born in 1813.
About to close the loop and get back to work, I searched "Francis Nelson" in my database to see who I listed as his current father. What I then noticed was pretty fantastic. The birthdate listed for Francis Nelson on my ancestry.com database was November 29, 1814. I'm pulling my hair out now because I don't know where I got this date from!!!!!!
In any case, the La France record also lists the date of birth as 29 Nov 1814. Either this is an exact match, or I'm fooling myself and its copied from the same source. I'm going to dig a bit deeper for the source of that birthdate but we might have an answer.
Complicating things, though, is that I just reviewed my notes and 3GRGR's last wife said that Julius had a brother named Francis . . . grrrr.
UPDATE: I've gone back to earlier backups of my FTM 2012 file on my computer and it looks like the birth date for Francis Nelson pre-dates my noticing the date of "Francois"'s birthday. Still not conclusive proof that they come from independent sources and are therefore corroborating, but at least it eliminates the idea that I personally and directly just copied it from the same source twice.