The heiress turned fashion designer and her fiance were outed Wednesday by her big sis, reality-TV star Paris Hilton.
"Congratulations @NickyHilton on your engagement! I'm so happy for you! You will be the most beautiful bride! Such a lovely couple! Love you both so much!," Paris wrote on Instagram, sharing a pic of her sister and her beau.
Rothschild hails from a famous European banking family. Nicky Hilton's great-grandfather is Conrad Hilton, the founder of the global hotel chain, and her dad is Rick Hilton, the chairman and co-founder of real estate brokerage Hilton & Hyland. Her sister, of course, is she of the infamous "One Night in Paris" sex tape as well as a slew of short-lived reality shows.
The celebutante and Rothschild began dating in 2011 after meeting at the wedding of model Petra Ecclestone and James Stunt in Italy, and Italy is where he proposed during their anniversary-weekend trip, Us Weekly reported.
"He took her out on a boat into the middle of Lake Como and he proposed, got down on one knee and everything. It was incredibly romantic and beautiful," a source told the mag.
Nicky Hilton has walked down the aisle before, though that union was annulled in 2004. The Nicholai designer was 21 when she wed childhood friend Todd Andrew Meister during a weekend romp in Las Vegas but ended that union nearly three months later, according to People.
Here's to history not repeating itself.