I wanted to do the same thing. I just chose another sensor (door open/closed) that I figured my son was most likely to use. So theoretically when he returned home and opened the door the Happy Birthday message would play.
But my in-laws got here first and left the door open. So as soon as my son “returned” (which was 500’ away in reality) the message played.
They told him about, but it wasn’t the same. Have to wait 'til next year.