Invited 22 years late

There was this article in firstcoastnews.com that talked about how a lady, Theresa, just recieved the invitation to her nephew's high school graduations 22 years ago. Her family just thought she did not respond to the letter because she lived in Oregon and they were in New Jersey. The thing is that the letter was even opened before she ended up recieving it. I really wonder what had taken the letter so long to get to her house; they say that it may have been stuck in the machinery or misrouted. But how could the letter be stuck in a machine for that long, you would think it would be noticed. In the end though Theresa was just happy to get something, for the first time, that she had lost.