"Marko and I are overjoyed to welcome Sienna into our family, and Valentina is looking forward to becoming a big sister," said the Brazilian supermodel via her rep to USWeekly.
The bundle of joy was born at 1p.m., weighing in at a healthy 7 lbs. on arrival.
Sienna joins sister Valentina, 2. Mom is said to be "doing well."
Adriana and Marko tied the knot three years ago in Jackson Hole, Wyoming on Valentine's Day.
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- Adriana Lima
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