Conversation so far:
Where was David McCullough born?
McCullough was born in the Point Breeze neighborhood of Pittsburgh, Pennsylvania.
What did they try next?
the son of Ruth (nee Rankin) and Christian Hax McCullough.
He is of Scots-Irish descent.

Question: What did they say?
Self-contained rewrite: What did Ruth (nee Rankin) and Christian Hax McCullough say