Did I solve it?

Ancestry. Ireland, Catholic Parish Records. 18 May 1824.

The image above from 18 May 1824 shows Bridget (Brigidam in the Catholic naming), daughter of Daniel Gannon and Maria Hanley in the diocese of Elphin, County Roscommon, Ireland. Sponsors were listed as Thomas Hanley and Margrette Kelly. If I am correct, this entry shows my 3rd-great-grandmother Bridget as she's brought before the church with her parents. If I have this right, Thomas would have been Bridget's uncle, and I've looked at him before, as Bridget lived next door to Thomas in the 1850 US Census in La Salle County, Illinois. This would also mean Timothy Hanley, the other neighbor in the 1850 US Census, the soldier sent to India via South Africa, was also her uncle.

There's a lot of "ifs" still to cover, but so far, the DNA is lining up with this hypothesis.

I examined this family back in June 2024, but it has taken a while for the DNA analysis to catch up to the paper trail. At the time I followed a hunch that Bridget was likely from a town near her first husband Patrick Dooner, who lived near Termonbarry, Roscommon, Ireland. It is unclear where Bridget and Patrick were married. So far I have not found a marriage record for them in Roscommon or Longford. It's possible they just eloped, or married elsewhere, even in England before arriving in America.

Using HD, an ungrouped 44 cM match in common with my Dad, I looked at both his shared matches of matches, and his own tree, to connect back to his great-grandfather Edward Gannon, born in Kilbarry, Roscommon in 1849.

Another generation back from Daniel Gannon, his father Thomas Gannon, born about 1770, was from Longford, Ireland.

Maria as a sister of Thomas and Timothy Hanley makes so much sense. This is why Bridget would have been living next door to them in 1850 with her infant Michael Dooner. There's also the group of matches connected to Philip Hanley, descending from Martin Hanley Sr (1810-1873). Martin Hanley was also from Roscommon. Philip is a 39 cM match with EWM, a 1C1R with my Dad, descending from his uncle Lowell O'Brien. My Dad and Philip have 23 cM in common, along with 17 cM in common with his sister.

If the hypothesis holds, Bridget's parents were Daniel Gannon and Maria Hanley, my 4th-great-grandparents. It also means I likely have the names of my 5th-great-grandparents, Thomas Hanley and Anne. These people were listed together in the Griffiths Valuation entry for Kilbarry, Parish of Termonbarry, County Roscommon. The family names Gannon, Farrell, Hanley, Cox, and Igo/Egan, show up repeatedly in DNA matches. I previously described about how Anna Maria might have been a name of Bridget's mother, based on Irish naming patterns and her children. If the hypothesis is correct, her first child with John O'Brien combined the names of her grandmother Anne and mother Maria.

I have a block of Hanley DNA matches connected to Philip who went to Australia and tested at MyHeritage. There's another group closely connected to the Hanleys who descend from Finnerans and Egans (Igo) in Roscommon. Another group of DNA matches align with the surnames Casey, Farrell and Greeley in Longford. There's more to do to validate the theory, but it is looking strong based on the combined DNA mapping, chromosome triangulation, and the paper trail.

I've run the hypothesis through several tools from YDG, to Claude and Google Gemini. These are all supporting the current theory.