Brotherly bond transcends NFL rivalry: Ravens NT Kemoeatu donates kidney to Steelers brother

Tuesday HBO Real Sports is airing a documentary about Ma'ake and Chris Kemoeatu. Ma'ake as a nose tackle for the Baltimore Ravens, while Chris was on the Steelers offensive line. Their improbable football journey led them from Tonga to Hawaii to rival teams in the AFC North and ended when one brother sacrificed his career for the life of the other.

Achieving an NFL dream together could be one of the strongest bonds a pair of brothers experiences, but the Kemoeatu brothers now share an even stronger connection. In 2011 Chris was sidelined with a serious kidney ailment.

NFL players are not immune to illness. Kendall Simmons played his entire career with diabetes, needing insulin injections on the sidelines between plays. Ma'ake said of his brother, "He had to go into training camp and had to fight through the pain to get ready for the season."

Ma'ake, who had played into the NFL for a decade, stepped away from the game to save his brother's life by donating a kidney to him.  In 2014, Ma'ake explained, "When we found out he needed a transplant, we had to stop our careers because his health was most important to us."  While preparing for the transplant, Chris found out he had another serious health problem, one that could have been a silent killer. Before he could receive his brother's kidney, he had to undergo surgery for a heart condition.

It has been nearly a year since Ma'ake gave his brother Chris the gift of life. Though linebacker Paul Kruger of the Cleveland Browns plays in the NFL with one kidney, Ma'ake has accepted the end of his career and is directing his energy towards business and charitable ventures.

Though the health crisis ended the brothers' careers, it also fortified their bond. "I never told my brother I loved him until the surgery," Ma'ake said. "I was scared I would never see him again. Even though I felt the love, I felt now was the time to say it."

The HBO Real Sports that features the Kemoeatu brothers airs Tuesday, August 18 at 9pm ET/PT