The new mom stocks up in New York City. Plus: Ben & Jen, Nicole Kidman and more

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Sienna Miller, shopping in London's Primrose Hill neighborhood on Monday, displays what are sure to be fall's newest must-haves: a pom-pom cardigan and earthy shawl. Although she's been spending time recently with estranged beau Jude Law, her engagement ring was not part of her ensemble.