PREPARE cake batter and bake in 13x9-inch pan as directed on package. Cool in pan 10 min. Carefully invert onto wire rack; cool completely. Meanwhile, beat pudding mix and milk in medium bowl with whisk 2 min. Stir in Cool Whip. Refrigerate 30 min. or until thickened.
TRANSFER cake to cake board or tray. Arrange ladyfingers, side-by-side, down centre of cake to resemble 6 bodies laying next to each other in a bed. Spread pudding mixture onto top and sides of cake, completely covering cookies and cake. Attach fruit rolls to sides of cake to resemble a bed skirt.
PLACE 1 wafer at one end of each body for the head. Use decorating gel to draw the eyes, nose and mouth on each wafer. Tint coconut with food colouring; sprinkle at top of each wafer for the hair. Add jelly beans to top of cake to resemble a polka-dotted blanket. Keep refrigerated.