Conversation so far:
What was the controversy?
Jerry Lee Lewis's turbulent personal life was hidden from the public until a May 1958 British tour where a news agency reporter learned about Lewis's third wife, Myra Gale Brown.
What was turbulent about Jerry Lee Lewis's personal life?
The publicity caused an uproar, and the tour was cancelled after only three concerts.
Why did the publicity from when a news agency reporter learned about Jerry Lewis' third wife cause an uproar?
Myra Gale Brown was Jerry Lee Lewis's first cousin once removed and 13 years old – while Lewis was 22 years old.

Question: What was the issue with the marriage?
Self-contained rewrite: What was the issue with the marriage between Jerry Lee Lewis and Myra Gale Brown?