The notoriously private Spanish actress couldn't have planned her baby girl's low-key debut any better since most eyes were glued to London for days.
A rep said that the baby girl was born at the Ruber Internacional Hospital in Madrid. No other information was released.
Cruz, 39, and "Skyfall" villain Bardem, 44, who married in 2010, announced they were expecting in February.
"From the first second, you feel so much love," the actress told Vogue in June after having her first child. "It is a revolutionary experience. That's the best way I can describe it. It transforms you completely, in a second. Nature is very wise and gives you nine months to prepare, but in that moment, when you see that face, you are transformed forever."
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