Had dream of son father marrying his wife to which they have already been marrie

I had a dream I was decorating and dee jaying my,already married, son fathers wedding. He was marrying the same woman to which he has been married to in life.They were clearly either remarring or been together a long time in my dream because I announce them as the new old Mr and Mrs. We have been and still remain best friends in life. His friends and family did attend to whom which I too know in life. My mother was helping me to decorate the reception. So in this dream I did not see them marry I only knew they married because I was clearly in charge of dee jay and reception decor. I woke up laughing with my ex about a long standing joke. But the joke was only something from a previous dream about our son.