 In almost all drawings and Biddenden cake designs , the twins are shown as conjoined at both the hip and the shoulder . Although such a fusion is theoretically possible , in that twins fused at one point may form a secondary fusion elsewhere , no case of a viable double fusion has ever been documented . 
 In almost all drawings and Biddenden cake designs , the twins are shown as conjoined at both the hip and the shoulder . Although such a fusion <a href='drop_aux' title='1'><mark>is</mark></a>theoretically possible , in that twins fused at one point may form a secondary fusion elsewhere , no case of a viable double fusion <a href='been_done' title='2'><mark>has</mark></a> ever been documented . 
In almost all drawings and Biddenden cake designs , the twins are shown as conjoined at both da hip and the shoulder . Although such a fusion theoretically possible , in dat twins fused at one point may form a secondary fusion elsewhere , no case of a viable double fusion done ever been documented .