Sarah Ferguson is already experiencing an all-time low in her reputation, and one bombshell move could make it even worse. Over the last few weeks Sarah has, unsurprisingly, continued to make headlines. For various reasons too.

One of which was the fact that she was being supported by her friend Priscilla Presley. Not only was she given a key to Priscilla's guest house, but she was also reportedly given advice too.

And that advice was, and is, to write a memoir.

Well, of course the idea would have run through Sarah's mind already. I mean, look how much money Prince Harry made from Spare?

But I hope that as well as thinking of the money, she has thought of the potential damage it could cause too.

As a royal expert, and someone who writes about the Royal Family for a living, I can assure Sarah that writing a memoir is the wrong move. And is a move that needs to be avoided at all costs.

Why? Because it really could damage her last remaining royal relationships (if she has any) forever.

Not because the content would necessarily be harmful to the Royal Family, but because it shows one thing.

That Sarah is, yet again some may argue, willing to cash in on her royal relationships.

But this time, it could be something that the royals, particularly her daughters Princess Eugenie and Princess Beatrice, could struggle to forgive.

So, what do you value most Sarah? The money that could land in your bank account when you sign that publishing deal. Or the relationship you have with the family that you once belonged to?

Time will tell.