The 17-year-old hit the runway in a black velvet playsuit paired with ankle boots, and looked like a chip off the old block.
Lottie is signed to Storm, the agency that discovered her sister Kate at the age of 14.
According to the Mirror, Lottie was scouted as a model at Kate's wedding to Jamie Hince in 2011, and has since done a number of photo shoots for the likes of i-D magazine and Teen Vogue, as well as starring in the Red Valentino campaign.
She was joined on the PFW catwalk by Georgia May Jagger and her sister Lizzie Jagger, who are the current faces of the label.
Georgia tweeted her excitement at 'walking' with her sister on Twitter, writing, "I loved being in the @soniarykiel show yesterday! With my big sis @lizzyjagger XXX thank you so much."
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