I just saw the original on DVD last week & haven’t watched it with commentary
yet, so this may be answered there or in THHE II, which I also have not seen.
Till I find out tho- your thoughts- is Ruby actually a child of the Jupiter clan or a
child abducted from a pillaged family that the Hills-dwellers decided to raise instead of eat?
I tend towards the latter considering she both acts differently from them & they treat her differently. In the remake, there is a more definitive answer but it’s still subtle.
The remake Ruby, a pre-teen child rather than the late-teen/early 20s woman of the original, seems normal but if you look very closely around the
forehead & eyes, she is slightly mutated- thus probably born to the Hills-dwellers