Brad Pitt has reportedly purchased a portrait of Justin Bieber for his son Pax.

The 50-year-old Fight Club star bought the piece which was created by street artist Bambi for his 10-year-old son and the image shows the Beauty and a Beat hitmaker alongside the words ''Rebel without a clue''.

Speaking to The Daily Star newspaper: ''Pax loves Justin and so Brad thought this would be the perfect gift for him.

''Brad loves Bambi's unique style and this is his third purchase from her.

''When he found out she'd done a piece with Justin, he knew he'd have to get it for Pax.

''The Justin artwork is done on a panel of wood and he loves how unique it is.''

Meanwhile, Brad and Angelina Jolie - who also raise Maddox, 12, Zahara, nine, Shiloh, seven, and twins Vivienne and Knox, five together - are rumoured to star in their first film together in almost a decade.