Moss Jr. has taken her first steps into Super territory with a catwalk debut at Paris Fashion Week.
For her inaugural runway experience, Kate's 17-year-old sister Lottie joined the likes of It-models Gigi Hadid and Molly Blair in a low-key appearance for Sonia Rykiel.
Wearing a dark, flared velvet playsuit and her loose, blonde hair falling over her face, the teen's look was reminiscent of her famous sister's early catwalk years.
The significant move onto the Fashion Week circuit follows a print campaign for Calvin Klein last year - 22 years on from her big sister's famous CK shoot with Marky Mark.
Lottie, who was a bridesmaid at Kate's 2011 wedding to Jamie Hince, is the daughter of Kate's father Peter and his second wife Inga.
The Moss sisters appeared together last February on the front row at the Topshop Unique show.
Posting the image of her runway experience on Instagram, Lottie wrote: "Sonia Rykiel show today was amazing, such a good group of models and crew!"
Among that group were rock 'n roll royalty-come-top models Georgia Jagger and sister Lizzie Jagger and Keith Richards' granddaughter and Lottie's bestie, Ella Richards.
The show was staged in Rykiel's boutique, which had been painstakingly decorated in the style of a library, with floor-to-ceiling texts setting the scene for "the Sonia Rykiel woman, who is, among other things, an intellectual being."