If William Robert Porter Jr born 1744 is the son of William Robert Sr Esq born 1752 then William Sr was 8 years from being born when he conceived Jr. That is certainly impossible. I assume that to be a typo.
Updated birth dates for my well documented relatives indicates that the William Robert Porter Jr that I am interest in was born 1784.
Furthermore, the Joseph Porter who I am relatively certain is the correctly identified direct ancestor of me and my great grandparents is documented to be the son of William Porter and Mary Richey according to his death certificate:
"Ohio Deaths, 1908-1953," database with images, FamilySearch (https://familysearch.org/pal:/MM9.1.1/X8N4-YWR
: 8 December 2014), Joseph Porter, 04 Sep 1916; citing Hopewell, Muskingum, Ohio, reference fn 57975; FHL microfilm 1,983,756.
His wife is Susan Griffith, and they are positively identified in this document:
"Ohio Probate Records, 1789-1996," images, FamilySearch (https://familysearch.org/pal:/MM9.3.1/TH-1961-31184-927-12?cc=1992421
: 1 July 2014), Licking > Applications 1885-1897 vol 3-4 > image 248 of 532; county courthouses, Ohio.
There is a William Porter born 1814 who is the sibling of Joseph Porter born 1822 and the son of William Porter born 1784. Technically, I think the William born 1814 is probably III rather than Jr though he would likely have been referred to as Jr during his lifetime.
Looking at Pvt William Porter Sr Esq, it looks like he indeed does have a son, Joseph, who might have a brother William, but the Joseph who is a child of Pvt William Porter Sr Esq is married to someone other than Susan Griffith, has different birth and death dates, has different relations, and is not my direct ancestor. If Pvt William Porter Esq is an ancestor of mine then it would be likely that the Joseph I am a direct descendant of is named after the Joseph you're thinking of.