Bunton – aka Baby Spice - turned 46 on Friday (January 21).
To celebrate, singer turned designer Beckham posted a montage of images of the pair together over the years, from their early Spice Girls days to more recent times.
The montage was set to the group’s track ‘Say You’ll Be There’.
“Happy Birthday @emmaleebunton!” Beckham wrote.
“So many amazing memories together. We love you so much! Kisses xxx.”
Bunton replied: “The best!!! Love you all so much. X”
Other members of the Spice Girls also paid tribute to Bunton on her special day.
Mel C shared an old snap of the pair together early in their career, writing: “Happiest of Birthdays to the one and only Baby Spice.
“Oh the adventures we’ve had! Can’t wait for more!”
“Love you with all my heart,” she added. “Have a wonderful day.”
Mel also told Bunton she’d barely aged since the picture was taken, saying: “You haven’t changed a bit.”
Geri Horner called Bunton her “soul sister” as she posted two pictures of them together, one from a music video and a more recent black and white shot of them smiling.
Fans were thrilled to see throwbacks from when the group started out.
“Iconic!” posted one person on Instagram, while another wrote: “Spice Girls for life!”
Another said the photos were “so cool”, while another admirer said that the ‘Wannabe’ singers seemed to “age backwards”.
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