Victoria Beckham Smiles with a Dolphin

Courtesy Victoria Beckham

updated 07/03/2012 AT 11:45 AM ET

originally published 07/02/2012 AT 4:30 PM ET

It takes a lot to make Victoria Beckham abandon her trademark scowl. But the queen of the pout looked positively happy while posing with a bottlenose dolphin.

“Such a special day with the children swimming with dolphins!!! They are so beautiful!!!!” the designer shared on Twitter on Sunday.

Beckham, who is mom to Brooklyn, 13, Romeo, 9, Cruz, 7, and Harper, almost 1, told Interview magazine that her frown is just a facade.

“I created this persona and I’m very different from that,” she said. “I know I am a happy person. So I don’t get upset when people comment on the fact that I look quite miserable all the time.”

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