Conversation so far:
Where was Joshua Chamberlain born?
Joshua Chamberlain was born in Brewer, Maine.
Who was Joshua Chamberlain's mother and father?
Joshua Lawrence Chamberlain was the son of Sarah Dupee (née Brastow) and Joshua Chamberlain.
What day was Joshua born on?
Joshua Lawrence Chamberlain was born September 8, 1828.

Question: What was unique about chamberlins family tree
Self-contained rewrite: What was unique about Joshua Chamberlain's family tree?