Macca's a grandfather again as Stella McCartney welcomes baby no 3

Baby no 3: Stella is thrilled to be a mum again

Fashion designer Stella gave birth a baby boy, named Beckett Robert Lee Willis, in a London hospital on Tuesday morning.

A spokesman for the designer said mother and baby were doing well.

Beckett is the third child for the 36-year-old and her husband Alasdhair Willis.

Since marrying publisher Alasdhair in 2003, Stella has spent a majority of the last few years being pregnant.

After welcoming first child Miller Alasdhair James in 2005, she gave birth to their daughter Bailey Linda Olwyn a year later.

Stella worked right up to the birth and hosted a star-studded Christmas party at her flagship London store last month.

Giving herself only a few weeks to recover from the birth, Stella will debut her autumn/winter 2008/2009 winter collection in Paris next month.

Sir Paul has two other grandchildren from his eldest daughter Mary - eight-year-old Arthur and five-year-old Eliot.