The 39-year-old British fashion designer and daughter of Beatles legend Paul McCartney delivered her fourth child with husband Alasdhair Willis, reports femalefirst.co.uk.
The overjoyed couple have named the new arrival Reiley, who joins her three siblings – Miller, five, Bailey, three, and two-yaer-old Beckett.
The designer was recently inspired by her large family to make an affordable range of clothes for children which she wants to be “timeless”.
“Children’s clothes have become disposable in order to be accessible. I wanted to do affordable and accessible kids clothes that are still timeless with a great quality that you would want to pass down for generations,” McCartney said.