Let’s say that you meet someone once in your life. Random occurence.
For example, once someone helped me choose a bottle of Shabbos wine at the grocery store. That person did me a simple yet enormous favor. Sometimes I wish that I could go back and thank him so much. I hope he and his family are doing well.
Don’t they say that if you’re thinking of the Rebbe, z”tl, then that means that the Rebbe, z”tl, even in Olam Habah, is thinking of you?
Yet, maybe that doesn’t apply here… you could be thinking about someone else and that person could be thinking about someone who has helped him in his life.
Anything is possible.