Nicola Peltz Goes Shopping at Victoria Beckham's Boutique with Soon-to-Be 'Little Sister' Harper

Nicole Peltz/Instagram

Nicola Peltz took her soon-to-be sister-in-law Harper Beckham out for a fun girls' shopping trip — and the pair made sure to stop at none other than her soon-to-be mother-in-law Victoria's Beckham's clothing store.

Peltz, 25, and Harper, 9, snapped an adorable mirror selfie in a fitting room as they tried on some pieces at Victoria's London boutique. "had the best girls day with my little sister ❤️ ** @victoriabeckham your store is a dream," Peltz captioned the photo, expertly taken by Victoria's daughter, Harper.

The Transformers: Age of Extinction actress, who got engaged to Victoria's son Brooklyn Beckham, 21, earlier this month, loves her future mother-in-law's designs so much, she even wore one of her dresses during the proposal.

Brooklyn Beckham/Instagram Brooklyn Beckham and Nicola Peltz

When Brooklyn popped the question, Peltz donned a canary yellow Victoria Beckham ruffled silk cami dress (which is currently still available to buy for $1,960 at farfetch.com,960 at farfetch.com,960 at farfetch.com,960 at farfetch.com,960 at farfetch.com,960 at farfetch.com,960 at farfetch.com,960 at farfetch.com).

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"You’ve made me the luckiest girl in the world. I can’t wait to spend the rest of my life by your side. your love is the most precious gift. I love you so so much baby," Peltz wrote on Instagram when she announced the couple's exciting engagement news.

In his own announcement post, Brooklyn said: "Two weeks ago I asked my soulmate to marry me and she said yes. I am the luckiest man in the world. I promise to be the best husband and the best daddy one day ❤️ I love you baby xx.”

Brooklyn Beckham/Instagram

Victoria celebrated her eldest son's engagement by sharing the couple's romantic snapshot and writing a sweet message of her own.

“The MOST exciting news!!” she wrote alongside the photo. “We could not be happier that @brooklynbeckham and @nicolaannepeltz are getting married! Wishing you so much love and a lifetime of happiness 🙏🏻We all love you both so much x @davidbeckham @romeobeckham @cruzbeckham #HarperSeven 💕.”