ATLANTA -- The Salute to Greatness dinner Saturday night will have a special glow.

Martin Luther King III, the eldest son of civil rights leader Martin Luther King Jr., will announce that he has married longtime girlfriend Arndrea Waters and that the couple are expecting a baby daughter.

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The Salute to Greatness dinner is a big fundraiser for the Martin Luther King Jr. Center.

“This is great news that a grandchild of Martin Luther King is coming into the world,” said Isaac Farris Jr., president and CEO of the King Center and a first cousin of the King children. “Our legacy continues.”

King III married Waters shortly after his mother's passing, but the couple decided to keep the marriage private until now.

King III is the first of Martin Luther King Jr.'s four children to get married, and he will be the first sibling to have a child.