The proposed relationship of Wilhelmine Sagert as the mother of MR and ER is supported by DNA evidence indicating shared ancestry within the family lines.
Specifically, DNA evidence confirms a 1st cousin, once removed relationship between VK (a descendant of the ER ancestral line) and JR (a descendant of the MR ancestral line) with 698.03 cM of shared DNA across 24 HIR segments.
This match is consistent with their placement within these shared ancestral branches.
Further support for shared ancestry within the MR and ER lines is provided by an additional 3 DNA confirmed relationships among other tested descendants tracing back to these lines.
Additional relationship details are visible to users who are logged in and are part of the DNA tested descendants.