It's her newly born baby daughter, Apple Blythe Alison Martin, reports People magazine.
Paltrow and her husband Chris Martin -- of the British band Coldplay -- became her proud parents on May 14.
Although it was a 'long labour', the Oscar-winning actress (Shakespeare in Love) and her daughter, who weighs about 4.5 kgs, are in good shape.
Fans and media persons gathered around the London neighbourhood to get a glimpse of the celebrity baby.
While the reason behind naming the child Apple is unknown even to the parents, the middle name has been derived from their respective mothers -- Blythe Danner and Alison Martin.
What's more? Coldplay recorded and shot a song especially about the birth, under the alias The Nappies, adds People.
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