I'm a little confused- how does it get messed up? I thought that when we pour in the sand it gets mixed up together regardless & this is the beauty of it- that they become together as one- "...As these two containers of sand are poured into the third container, the individual containers of sand will no longer exist, but will be joined together as one. Just as these grains of sand can never be separated and poured again into the individual containers, so will your marriage be."