Hospital error

My mother-in-law was discharged from the R------- hospital today and my sister-in-law has medical power of attorney so my sister-in-law was sent the discharge papers for her mom.  Attached to the discharge form were the discharge forms of several other patients which contain sensitive information. of course. 

I'm not naming the hospital but not to protect them but to protect me.  Most likely my sister-in-law will return the papers to the hospital and I'll end up in an indefensible position because I'll not have proof of incompetence.  Let us just say it be better that my sister-in-law was the one the papers went to than maybe someone else.