Pippa Middleton, aka Auntie Pippa, is thrilled at the arrival of her nephew, Prince George, and has already been helping sister Kate in her early days of motherhood.
Pippa, 29, says she's "very excited about my sister's baby" and "so happy to be an aunt, as I love kids," a source close to the Middletons tells PEOPLE.
Pippa has shown her love for children many times. She is an ambassador for the Mary Hare School for deaf children, and last Halloween hosted an afternoon kids' party at London's Daunt Books.
Reporting by SYDNEY BERGER
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