I Almost Had a Heart Attack!

While opening the mail a couple of days ago, I found an envelope from the IRS. With increased heart rate and shaking hands, I slowly opened it and began to read the papers inside. My heart couldn't decide whether to STOP or SPEED UP - I owe what????? I owe $3,978 from 2007????? How could that be?
I quickly called by SIL [the CPA] who explained that the IRS was wrong!!! I do not owe them anything!!! She will write an explanatory letter and settle the matter. YEA!!!
So, all is good now. I am once again breathing normally with a steady heart beat. Mail can be scary sometimes.