<□>□eyond the□r individual success, □□ssica and K□ystal hav□ al□o□colla□o□ate□ on va□iou□ projec□s□together. Fro□ photo□hoots and□magazine c□vers □o re□l□t□ □V shows □nd □harity□event□, the si□ters □ave □□o□en t□□t they are□a for□e to be rec□oned with when they join□forces. The□r□s□ared □i□i□n and □utual□respect for e□ch other's talents□□ave only □□ren□thened□th□ir □o□d over□the years.