Is it normal to have an intense desire to be spanked by my mother-in-law?

My wife and I have been married for over twenty years. We have a great relationship with each other and each others family. I have always found her mother attractive and my wife knows this.

But over the past few years I have had an ongoing fantasy of her spanking me. The fantasy is simple; I am standing in her living room with my pants and underwear around my ankles. My mother-in-law and my wife are standing behind me. She spanks me very hard several times and when she is finished she hands the paddle to my wife and says, "Now you do it." And my wife spanks me after that but it is not hard enough to satisfy her mom. She tells my wife, "Harder!" And my wife continues to spank me until she gets it right. In this fantasy my mother-in-law is teaching my wife to paddle me and telling that she needs to do this regularly.

My wife has paddle me a few times playfully. But she has never really gotten into it like I wish or hoped she would. However, her mother has always seemed like someone who would enjoying spanking a man. I think that is one of the reasons I imagine her in my fantasy. (I know she would like to spank her husbands ass! LOL) Anyway, that is my fantasy and I would like to share tell my wife about it. Not because I want to talk her into. But, I would like for her to tell her mom that I have this fantasy. Not that she would ever say "hey mom would you do this?" but tell her in a humors way. As something for them to joke around about like "Can you believe he has thought?" I imagine my wife telling mom and both of them teasing me about it. Saying things like, "You better do what we say or you will get a spanking."

Honestly, I do not think they would ever actually spank me with my pants down. But I do think they would tease me for having that desire. And that would almost be as good as her actually doing it!