They’ll all be called Barbie, but it’s the curvy one—with meat on her thighs and a protruding tummy and behind—that marks the most startling change to the most infamous body in the world.

One of the greatest tools that a girl can have is the support and encouragement of her peers,' said Krista Berger, Senior Vice President of Barbie and Global Head of Dolls, Mattel. She added ...