Confirmed : Angelina Jolie givs birth to twins – a boy named Knox Leon and a girl named Vivienne Marcheline

"Saturday was a great day for all," Dr. Michael Sussman says. "The babies are good, as is Angelina."

Knox weighed 5.03 pounds and Vivienne weighed 5 pounds, Sussmann adds.

And Jolie has already started to receive visitors. "Angelina's brother [James Haven] has been here this morning," a hospital insider tells US.

"There is a buzz at the clinic. The babies are resting, as is Jolie. They haven't [been] crying yet, so it just feels very peaceful."

Jolie, 33, gave birth via a Cesarian section at the Lenval Hospital on the French Riviera.

The Cesarian section was moved up from its scheduled date "for medical reasons" so the babies would be born "in the best conditions," Sussmann explained.

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