"‪#‎Ajsoars‬ is in Heaven, where he belongs... ‪#‎ajsoar‬ ‪#‎P3‬ ‪#‎MyFirstSuperHero‬"

A.J. was diagnosed in June 2014, when he was just 6 years old.

The Peterson family received an outpouring of support through social media, as they publicly documented the young boy's heath struggles.

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Peterson was a star running back for Georgia Southern from 1998-2001, and played for the Chicago Bears from 2002-2009. Peterson also had brief stints with the Minnesota Vikings and the Virginia Destroyers.

Supporters have been leaving condolences on the Facebook page AJ Soars, Prayers for AJ.