Ferne and Billie are wearing matching flared denim jeans and similar white T-shirts in the snap, and are posing together at the seaside.
The girls were in Year 8 at school at the time, making them either 12 or 13, and Ferne has admitted they wore their identical trousers at any given opportunity.
Sharing the picture on Twitter yesterday as part of the site's 'Throwback Thursday' trend, Ferne said: "This is the best #tbt you'll ever see. Me and @BillieFaiers Year8. We lived & died in these Miss Sixty jeans."
Ferne also added a total of NINE emojicons showing a face crying with laughter - just to emphasise her point!
After taking a look at the photo, Billie - who is now pregnant with her first child - replied to her pal: "Hahaha I think we can safely say we blossomed... The matching flared jeans!!! Brilliant!! Xx."
While we recognised Ferne straight away, Billie looked very different during her school years thanks to her natural brunette hair and fringe. Aww, cute!
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