I hate to be that guy, but... "Junior is used to distinguish a son with the same name as his father. The following conditions apply: The Junior must be a son of the father, not a grandson. The names must be exactly the same, including the middle name. HT ThoughtCo.com
My stepdad and his son shared same first and last name but not middle. We differentiated by using Sr. and Jr., but neither of them used it as a suffix which appears to be the same in this case.
I hate to be that guy, but... "Junior is used to distinguish a son with the same name as his father. The following conditions apply: The Junior must be a son of the father, not a grandson. The names must be exactly the same, including the middle name. HT ThoughtCo.com
My stepdad and his son shared same first and last name but not middle. We differentiated by using Sr. and Jr., but neither of them used it as a suffix which appears to be the same in this case.