Robert Downey Jr. and his wife, Susan. (Chris Pizzello/AP)

The “Avengers” actor and his wife, Susan, welcomed their first child, a son, Tuesday in Los Angeles, his rep confirmed to People.

The couple announced the pregnancy in August. Downey let it “slip” to Jay Leno in December that he and his wife were expecting a boy.

The actor has an 18-year-old son, Indio, from a first marriage. The newest Downey also has an offbeat name: Exton Elias.

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Beyonce gives birth to daughter Blue Ivy Carter

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Robert Downey Jr. with wife Susan. View Photo Gallery:  See more photos of the celebrities who have recently welcomed children or are expecting.