The Twelfth Night Ball returns to Prairie du Rocher this Saturday, Jan. 6, from 8 p.m. to midnight. The Prairie du Rocher American Legion offers a cash bar and will have several wines especially selected for the ball. Commemorative glasses will be available for sale at the door.   Music will be provided by Cousin Curtis and the Cash Rebates. Doors open at 6 p.m., with cake served about 9 p.m. Admission is $10 for adults, or $5 for ages 14 and under. The family price is $30. The public is welcome, and costumes are not required.  No coolers or outside liquor are allowed.