Newest ancestor is almost an oxymoron, since all of us were born with all the ancestors we will ever have. But in genealogy, we are learning about our ancestors so when we find a branch we didn't know about yet, they are new to us. I have been at this most of my life, so I don't find as many new ancestors as I did in the beginning, but there are still surprises and discoveries.
My newest ancestor is named Owen Gray b 1783 in Roscommon Ireland. We had stories from my grandmother, some very detailed, and it has been gratifying to be able to document them. She knew a lot about his service at Waterloo, and could describe the battlefield with stories that had come down in the family. We knew he had come to Quebec, and that he had one son and three daughters. But we never knew his first name, his origin in Ireland, his military unit. We were told we were Scotch Irish, certainly true for part of the family, and we thought he'd be from County Antrim, where we knew some of the relatives were from. Roscommon is not Ulster, though close enough.
A new name to learn about, maybe a future trip to Ireland, but certainly something to research here. Another ancestor who died in Canada, and perhaps a grave to discover. And where will we find his wife, whose name my grandmother knew, Annie Clark, but about whom we can find nothing? We can find the wife he married late in life, and we have hope of finding the Canadian aunts, or their offspring.
It is not exactly like the birth of a new baby, finding a new ancestor. And yet it is. Everything old is new again.