superstition suggests you'll get seven years of bad luck if you break one!
Mirrors were once believed to be windows into other worlds – often worlds where things were the wrong way around. People may also have been frightened that a person’s reflection shatters when a mirror is broken. One theory is that they thought breaking a mirror was like breaking your soul.
Some people also believe that mirrors should be covered up during births and funerals, for fear the person’s soul might escape through them to another realm.