A Black Friday Kind Of Birthday

I went up to Fort Collins this afternoon to celebrate Thanksgiving with my sister Susan and brother-in-law George.  Since today is George's birthday, we decided to celebrate both events at the same time.  When I first met him, George was 10 years older than  me.  Now he tells me that he is actually 10 years younger than I am.  Susan says this has something to do with Quantum Physics and Einstein's Theory of Relativity.  Isn't science wonderful?