Brad Pitt buys his and Angelina Jolie's son Maddox a motorbike for his 11th birthday

Brad Pitt is a father of 6

Brad Pitt treated his and Angelia Jolie's son Maddox to a motorbike on his 11th birthday at the weekend.

The actor - who's currently living in Surrey with his family while Angelina, 37, shoots new film Maleficent in the UK - was spotted looking at children's bikes in Ruislip in June and eventually chose a Suzuki DRZ-125.

'Brad took him into the garage and there the bike was with a bow on it. Maddox was over the moon and couldn't wait to try it out,' says a source.

'He was riding it around all day at the house, tearing up the lawn.'

Brad, 48, is a keen rider himself and owns a number of motorbikes, including Ducati's Desmosedici RR and Monster 696 models.

He's built a motocross trail in the grounds of his and Angelina's French estate Chateau Miraval to ensure Maddox has somewhere to use his expensive new toy.

'He was down at the house the other week and got the builders to dig him a muddy trail all through the woods and around the lake,' the source tells The Sun.

'Brad was just as excited as Maddox about it, though - he's put in little jumps and puddles so they'll get really muddy.'

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Anna Duff