efforts. >> reporter: when life is saturated by loss, when words fail. ♪ >> reporter: sometimes music speaks. >> hymns of hope inside a houston house of worship. songs replacing sorrow. >> i remember when my town, not too many towns away from here, got devastated by hurricane katrina. >> reporter: almost 12 years ago to the day singer harry conic jr. led compassion to a devastated new orleans. >> good luck to you, baby. good luck rsh wrinchts now he is one of thousands helping houston rise. a city that once opened its arms to katrina victims. >> this was the way to pay it forward. >> oh, yeah. i'll never forget houston for that. i have always loved houston. >> reporter: as the waters recede, volunteer efforts have flooded in. thousands showing up day after day in shelters and neighborhoods left in sham bells. >> i really appreciate that because we are really hungry.