The proposed relationship of Robert Gruenke as the father of EBG and DG is supported by DNA evidence indicating shared ancestry within the family lines.
Specifically, DNA evidence confirms a great aunt / uncle relationship between JG (a descendant of the DG ancestral line) and AB (a descendant of the EBG ancestral line) with 1005.06 cM of shared DNA across 34 HIR segments.
This match is consistent with their placement within these shared ancestral branches.