The actress is pregnant for a second time and is thought to be expecting twins. The couple already have adopted children Maddox, 6, Pax Thien, 4, Zahara, 3, and biological daughter Shiloh, 23 months, NOW reports.

Brad, 44, is said to have issued her with an ultimatum: 'No more kids our family's complete.'

'Brad loves being a dad and enjoys nothing more than spending time with the children,' says a source.

'But he's constantly tired from working so hard and then mucking in at home. All the sleepless nights are taking their toll.'