By Alexandra Whittaker
Oct 12, 2018 @ 6:45 am

Princess Eugenie's wedding had a healthy mix of expected star guests (see: Kate Middleton, Meghan Markle, and Princess Charlotte), and less expected surprises (see: Kate Moss). Adding to the mix of the latter is none other than American actress Demi Moore, who stepped out to support Eugenie on her big day.

Matt Crossick/Getty

While we can't say we expected to see Moore join the party, it was a welcome surprise when she walked into Windsor Castle in a maroon dress. Still, as we've learned, it's not completely out of the blue that Demi would be there.

According to People, Moore is good pals with both of Eugenie's parents, Sarah Ferguson and Prince Andrew, and she's been to Princess Beatrice's birthday parties before.

RELATED: Kate Moss and Her Lookalike Daughter Were Unexpected Guests at Princess Eugenie's Royal Wedding

Talk about star-studded.