Well, the specific answer I'm seeking is basically anything. I have only my great great grandparents names, James Armstrong and Mary Rankin, and that they were from Ireland.
I don't know when they were born. I don't know if they came here as a married couple or if they came as kids with family and met and married here. I don't know when or where they died. The biggest problem is that I don't find the family unit in any census records. In 1880, William Armstrong is already out on his own. I contacted the church in Bay Ridge that would have been most likely to have baptismal records and drew a blank.
I did find a family tree with a James Armstrong and Mary Rankin in Pennsylvania with sources to back it up, but they appear to be unrelated. The geography is just wrong as William Armstrong's 1930 death certificate showed him as living in Albany for 65 years. That would have made him no older than 8, so probably not even old enough to have been sent off to apprentice at some trade.
What I'm working on now is the first step in learning more about that branch of the family. I have a lot of "what ifs," some ponderings, and some speculation, but nothing solid. Even if all I have is a suspected occupation from a city directory, it will give me something new to go on.
If you have any suggestions I would sincerely love to hear them. I have so little to go on and their names are so common, its been difficult to get started on them.