And Yolanda King, her brother's oldest child, died from an apparent heart condition last year.

CNN: Sister remembers 'horrible moment' King was killed

Research will address an apparent medical paradox: NFL players are superior athletes in top physical condition.

WSJ: NFL Players Fund $100 Million Health Study at Harvard

It said its most distinctive effect is apparent in his curvy Cupid's bow mouth, and the condition would also have affected his mental development.

BBC: Peter the Wild Boy grave gets Grade II listing