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.
What did they say?
One of four sons, McCullough had a "marvelous" childhood with a wide range of interests, including sports and drawing cartoons.
What was his next weekened?
School and Shady Side Academy, in his hometown of Pittsburgh.
What was there next choice?
McCullough's parents and his grandmother, who read to him often, introduced him to books at an early age.

Question: What did they joke about?
Self-contained rewrite: What did David McCullough joke about