By now, we all know that the newest little heir to the British throne has arrived and Prince Louis is absolutely adorable. But something that isn't so adorable (depending on how you feel about horror movies) is the Jenny Packham dress that Catherine, Duchess of Cambridge a.k.a. Kate Middleton wore as she held baby Louis outside of the hospital for the big baby reveal.

Fans of classic horror movies immediately noticed that the Duchess' dress looked strikingly familiar to one worn by actress Mia Farrow in the 1968 drama/mystery movie Rosemary's Baby. The film, directed by Roman Polanski, has a cult following and was a major hit in its day.

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Spoiler alert! We hate to bring up spoilers in case you haven't seen this classic yet, but the plot is pretty important to the significance of Kate wearing a similar dress. The movie, based on a book by Ira Levin, follows a young married couple who become pregnant with their first child. Through a series of events, the wife becomes convinced that her child is "not of this world" and potentially harbors a dark presence. Eventually, she learns that the child she is carrying is the antichrist.

So you can see the reason behind the buzz.

"Anyone else notice Kate's dress is similar to the Rosemary's Baby dress?" Twitter user Jimmy Kalaitzis tweeted.

"Kate wearing the same frock as Rosemary did in "Rosemary's Baby"...hmmm should we be a little bit concerned..LOL..." another user, Suzie tweeted.

Rest assured, Prince Louis is a perfectly healthy (and 100 percent human) baby boy but for those who are superstitious or just really into Rosemary's Baby, this dress couldn't have been a good sign. We have to reason that neither Kate nor Prince William (or anyone on the Kensington Palace staff for that matter) saw the movie or they might have taken issue with the chosen wardrobe.

Another person that we're guessing never saw or simply forgot about the famous scary movie is designer Jenny Packham. She is one of Kate's favorite designers as Kate has chosen her dresses for all three of her baby reveals plus many other important events.

Red is a color that represents passion, love, family ties and strength. So we'll just stick with that as far as the symbolism of Kate's dress for Prince Louis' first hello to the world.

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