Mysterious John

I was born in Phoenix, Arizona. As an adult I had moved abroad and been away for a while. Once I was visiting my childhood home where my mother was still living. On that day, there were also my cousin, and with her some guy I did not know. I introduced myself to the unknown guy. He said: “I am John, don’t you recognise me? We spent so much time together as kids!” Also my mother and cousin wondered how is it possible that I do not recognise him. Nevertheless, even today I do not have a slightest memory of spending time with John as a child.