I'd draw the line at once a generation, although I think even that lacks originality.
I had a great grandfather named
Stephen.
-his son, my grandfather, was
Stephen, Jr.
-his son, my uncle, was
Stephen III "
Steve"
-his nephew, my cousin, was
Stephen "
Stevie"
...and another cousin was named
Stephanie
It's needlessly confusing imo. Names are supposed to differentiate one person from the next, so it just seems pointless to use the same name so many times in the same family, especially in the same generation.