When Prince Charles and Princess Diana were married, the public was fascinated with them as a couple. It was before the age of the internet, but the public still had no problem getting their fill of Chuck and Di. And that's because they were photographed almost constantly.

However, in most of their posed photographs, one odd thing keeps happening over and over. It's something you might not notice right away. Can you spot it?

This picture might contain a bit of a hint. In this photo, it looks like Diana was sitting down. However, Charles is standing.

Meanwhile, here's a candid photo of Charles and Diana together. Since they weren't specifically posing for a photo, something from this photo is decidedly different from the posed photos. Do you see it now?

In case you didn't see it yet, here's the answer. In most of their posed photos, Charles is seen as being taller than Diana. Like in this photo, Diana only comes up to about Charles' ears.

Or look at this photo from their wedding day. Charles is clearly seen as being taller than his wife. However, that's not how things were in reality.

But in this candid photo from their wedding, things are quite different. In reality, Charles and Diana were roughly the same height, at 5' 10".  So why the deception?

As you might expect, the reason for the trickery has to do with societal expectations when it comes to the height of men and women. In a male-female relationship, it's expected that the man be taller. But that's not always the case.

With that in mind, photographers would try to rig photos to make Charles looks taller than Diana. For instance, in this case, Diana is sitting down, making her unable to see eye-to-eye with the prince.

The height dynamic was even adjusted in this photo with Prince William as a baby. Diana is clearly crouching down while Charles is seated upright. This again makes Charles to be the tall one in the couple.

On the other hand, in this photo, Diana appears to be the one with the height advantage. However, the extra height might only be due to the big hair Diana was sporting at the time.

A royal stamp exaggerated the fake height difference even further. A photo of the stamp was tweeted out by sociologist Philip N. Cohen. The stamp is so far removed from reality that the rest of Twitter took notice.

It's unclear whether it was Charles' idea to have himself appear taller, or if it was the idea of photographers, or if someone else was overseeing the photographs. But either way, there must have been some sort of fear that the public would not accept that a prince could be the same height as a princess.

This person reported that they have Chuck and Di doll book. The Charles doll included shoes that came with lifts. So perhaps the height difference (or lack thereof) wasn't such a secret after all.

Meanwhile, someone else noticed something about the stamp that has nothing to do with height. And that's the fact that the stamp features a cameo appearance by Charles' mother. Can't a couple enjoy a little privacy?