The Donaghmoyne Network

Why This Research Is Challenging

Connecting these Donaghmoyne families requires pushing beyond the limits of what Irish genealogy and autosomal DNA can typically provide. Several factors make this research particularly daunting:

The Irish Record Gap: To prove sibling relationships between Henry Hamall (married 1841), Owen Hammel (married 1846), and James Hamill (father of Susan), we need to identify their parents—a couple likely married around 1810–1815. But Catholic parish registers for Donaghmoyne begin only in 1835, and most civil registration starts in 1864. The Great Famine (1845–1852) and subsequent emigration scattered families before comprehensive records existed. We're searching for ancestors in a period where few records survive.

The Only-Child Problem: The Henry Hamall and Mary McMahon line presents an extreme genealogical bottleneck. While Owen Hamall (1847–1898) had at least one sibling who survived to adulthood—his sister Mary Ann Hamall Byron, through whom all four of our DNA matches descend—his half-brother William Thornton (through Mary McMahon's remarriage) lost three children in early childhood and left no descendants. Owen's own line narrowed dramatically: his son Thomas Henry (1880–1938) had only one child, Thomas Eugene. His daughter Mary Hamall Holland had two sons, but neither left descendants. Thomas Eugene had one son, Thomas Kenny, who married Barbara O'Brien and had six children—five of whom have tested. But here's the problem: those five testers have no 1st cousins, no 2nd cousins, and no 3rd cousins to compare with. The family came within one generation of extinction, and while it survived, the lack of cousin matches makes triangulation nearly impossible within the Chicago Hamall line itself.

Autosomal DNA Limitations: Autosomal DNA is powerful for relationships within 4–5 generations, but we're looking for common ancestors 7+ generations back (c. 1790 or earlier). At that distance, autosomal DNA becomes unreliable—many descendants won't share any detectable DNA even if they're truly related. The cross-network matches we've identified (8–34 cM) are at the edge of what autosomal testing can meaningfully detect.

The Reconstructed-Kit Resolution: The case study has addressed the autosomal-DNA distance limitation through reconstructed paternal kit methodology (see Chromosome 2 Triangulation Analysis), which captures the subject's father's paternal genome from his children's DNA and provides a direct comparator for paternal-line matches. The cross-line MRCAs in this case study likely sit 6–8 generations back (c. 1790–1820), and at that distance segments become smaller and harder to interpret with confidence. The reconstructed-kit methodology has now established the network-level finding. What it cannot resolve, even at this rigor, is the specific identification of pre-1830 ancestral couples — that requires documentary research.

Research Gaps & Next Steps

The primary gap in this research is the parental generation. If Owen Hammel, Henry Hamall, and James Hamill (father of Susan) were indeed brothers, their parents likely married in Donaghmoyne around 1810–1815. Identifying this couple would definitively establish the sibling relationship.

The relationship between this proposed sibling group and James Hamill Sr. (1827–1914) also requires clarification. The indirect DNA connection patterns, combined with the younger birth year of James Sr., suggest he may connect through a collateral line—perhaps as a nephew or cousin rather than a brother.