Stella McCartney: Bump Under Wraps!

On her 39th birthday, Stella McCartney and her husband Alasdhair Willis were photographed in London on Monday morning (September 13) doing the school run. The designer, who rocked a pair of fashionable jeggings, kept her bump under wraps. The couple - who were also spotted on the school run the following morning - have three kids, Miller, 5, Bailey, 3 1/2, and Beckett, 2, and are expecting their fourth child this fall.

McCartney is also launching her new children's line on November 3. The collection will be aimed at both girls and boys up to age 12.

"As a brand with many working parents in the team, I wanted to create a desirable, fun, wearable kids' collection that was affordable," she tells VogueUK. "I feel like all the timeless children’s wear is reserved for the expensive brands and that does not sit well with me, kids and parents, aunts, uncles, friends, should all be able to have access to Stella McCartney Kids clothes. We have tried to make that possible in this first collection, and hope it is enjoyed!"

Prices range from $26 for t-shirts and around $120 for one of the coats. You'll be able to buy the clothes at www.stellamccartneykids.com as well as in all her stores.