The two brunettes were spotted making the most of their night out together on Thursday (4 July), where they enjoyed a live DJ set, picked up some free goodie bags and rubbed shoulders with celebs such as Preeya Kalidas and Mis-Teeq's Su-Elise Nash.
And the siblings couldn't resist playing up to the cameras either while they were there.
In one snap taken at the launch party, held in Covent Garden, London, Sophia and Zara can be seen puckering up to each other and kissing on the lips. How's that for a bit of sisterly love?!
Sophia - who quit Made In Chelsea following a romance with co-star Francis Boulle - was dressed casually for the occasion, wearing her favourite pair of patterned trousers (which she was spotted in twice last month) and a slightly see-through black polo neck top.
Her model sister Zara opted for a laid back look too and wore an interesting pair of white and brown boots, with denim cut-off shorts and an oversized checked shirt.
What do you think of Sophia and Zara's outfits? Let us know below!
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Copyright: WENN Daniel Deme