Sandra Bullock and Son Louis Dress Up as Pirates!

Credit: BONG/GSI Media

Shiver me timbers: Lil' Louis Bardo is a pirate!

Dressed for the high seas, the adorable 21-month-old and his mom attended a friend's birthday party in the Brentwood area of Los Angeles, Calif. Sunday. (See more photos at Just Jared.)

Sandra Bullock joined in on the fun, sporting a pirate's hat as she toted around her pride and joy. The 47-year-old actress, who stars opposite Tom Hanks the upcoming movie Extremely Loud and Incredibly Close, adopted Louis Brado from New Orleans in January 2010.

Nicknamed her "Cajun Cookie," Bullock says she "got lucky" with her her son. "Motherhood has made me a better person," the star has said. "I really appreciate where I am."