Question: The two children of Cassius Marcellus Clay Sr. and Odessa Grady Clay was a three-time World Heavyweight Champion and who?
Sentence (from "Odessa Grady Clay"): Odessa Lee Clay (née O'Grady; February 12, 1917 – August 20, 1994) was the mother of three-time World Heavyweight Champion Muhammad Ali and Rahman Ali, and the grandmother of Laila Ali.
Relevant evidence: Yes