This was an idea I was thinking of using in my current story at a later point. That the Royal Guard ponies are not technically ponies but golems created by the princess in pony form.

The idea was inspired from the story Seeing the Pattern 2 by a few facts that were present in the story.
1. While the royal guard are their to "protect" the princesses it is revealed that since the sisters are gods (at least in this story) they have no fear of being harmed by mortals.
2. Luna seemed to regard them as if they were their only to serve.
3. They are all twins. Each guard has a twin counter part.

While the points mentioned above kind of lead to the idea other things in the show also point to it. For example all the royal guard ponies have either a white coat or a brown coat and many of them match each other.

So I came up with this idea that the royal guard are actually golems (although I didn't originally refer to them as a golem) that serve the princesses.

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So what are your thoughts on this observation (idea).

Also feel free to throw your observations into this forum too.

3563638 I had a similar observation. In my story, I solved it just by making them very dedicated due to the family pressure. Being a royal guard kind of runs in the family, that's where those similarities come from.