Interesting family history very similar to mine. In every instance for about 5 generations, I am descended from the youngest child. It really stretches things out.
Had a lot of trouble on my mom's side because they tended to have children late. My great-aunt (my maternal grandfather's sister) didn't even know the name of her maternal grandfather, because their mother was the youngest of 9 children, and suffered from classic Alzheimer's (early onset of dementia, in her 50s) so she couldn't tell them a thing about the family.
To further complicate matters, the family was from South Carolina, which didn't keep official birth or marriage records until after WWII (that's not a typo - marriage licenses were introduced in 1948, I think). But I was able to go through newspaper announcements, land records and U.S. Census handwritten returns and figure out his name, where he was born, his wife's name, and the names of all his children. People think that genealogy is sort of a silly hobby, but it was all worth while when I saw my great-aunt's eyes light up. She was SO pleased that she finally knew her grandfather's name.