The Formula One heiress announced her happy news via Instagram on Tuesday afternoon (18 March), alongside a beautiful photograph of herself cradling her precious little bundle.
Tamara wrote: "Welcome to the world Sophia, our beautiful little girl, born yesterday. 6lbs 9oz. Proudest day of our lives, never felt love like this."
What a cutie pie little Sophia is. And just look at that head of hair!
It's the first child for Tamara, 29, and her businessman husband Jay Rutland.
Brunette Tamara married Jay in the French Riviera last June, then made their vows official at the Chelsea Old Town Hall. Their pregnancy announcement came a few months later.
We knew the birth was imminent as Tamara had tweeted on 15 March she was enjoying a last night out with Jay before "two becomes three".
Tamara was thrown a baby shower by sister Petra earlier this month; a pink and white-themed extravaganza at plush London venue The Orangery at Kensington Palace.
And no doubt Petra's been passing on plenty of mummy advice seeing as she welcomed her own daughter, Lavinia, last year.
Congratulations to Tamara and Jay!
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