Fashionista-in-training Harper Beckham got to practice her (newly-acquired) walking skills in an extra special venue Saturday afternoon.

As her mom, Victoria, got ready to show her Spring/Summer 2013 collection at the New York Public Library's storied Astor Hall, she snapped a photo of Harper, 14 months, toddling down her makeshift catwalk.

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"Testing the runway!" Beckham, 38, wrote in the caption accompanying the picture.

In the exhausting days leading up to her show, Beckham -- busy balancing last-minute adjustments to her designs with Fashion Week appearances -- admitted the sleep deprivation was starting to catch up with her.

"After three hours of sleep I still feel like an old bag!" she tweeted Friday, sharing a picture of herself wearing a giant handbag over her head as she typed away on her laptop.

Her hard work paid off on Sunday however -- show attendees had nothing but good things to say about Beckham's latest designs.

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As a Los Angeles Times fashion critic wrote, "A knockout. Beckham's collection is really evolving . . . The brand isn't just about Beckham anymore, it's about her customer."

This article originally appeared on PIC: Aww! Harper Beckham Walks Runway Before Mom Victoria's Fashion Show