All I can tell you is what was shown to me in the vision. They group the handheld families together, Gameboy Advance was considered part of the Gameboy line, but DS was considered a new "third pillar". The DS line had a whole family of systems, and so does the 3DS line. They don't count each entry in the Gameboy, DS or 3DS line as a new family.
Each new home console is on its own though, even if the names are similar. They too are their own family, like the Wii and Wii Mini or the NES and NES2 edition.
Consider each numbered entry to be a "family". The NX is the tenth family, and it's special because it's when the two main families come together in a cross "X".
Virtual boy and Game and Watch don't count because neither is either a home console or a portable console.
