Jolie and Maddox spent a wonderful day celebrating his 5th birthday August 5

New mothers Angelina Jolie and Gwen Stefani are swapping weight loss tips.

The 'Tomb Raider' actress and her partner Brad Pitt met up with the blonde singer and her husband Gavin Rossdale during the July 4 weekend and the ladies shared ways to shed the post-baby weight.

Gwen - who has a two-month old son called Kingston James - is reportedly advising Angelina to eat plenty of fresh vegetables and fresh milk, while Angelina - who gave birth to daughter Shiloh Nouvel on May 27 - has been stressing the importance of exercise.

A source told America's Life & Style magazine: "The two of them are often on the phone comparing their weight losses. Angie prefers to work out more than Gwen, but they both agree that healthy eating is of the utmost importance."