The proposed relationship of Elizabeth Short as the mother of
Thomas Jefferson Short and
James Robert Short is supported by DNA evidence indicating shared ancestry within the family lines.
Specifically, DNA evidence confirms a distant cousin relationship between KS (a descendant of the James Robert Short ancestral line) and KG (a descendant of the Thomas Jefferson Short ancestral line) with 15.62 cM of shared DNA across 1 HIR segments.
This match is consistent with their placement within these shared ancestral branches.