Robin Thicke's three-year-old son wants to be just like his dad when he grows up and is already saving up to buy a concert stage.

Little Julian Fuego insists on accompanying his father to soundchecks before big gigs and has already made his mind up about what he wants to be.

Proud mum Paula Patton explains, "He's obsessed with it... He said one day, 'I wanna save up my money to buy a stage and I'm gonna have some guys...' He meant the band."

And the little guy has already started writing songs that he hopes will one day compete for a chart place with the Blurred Lines hitmaker.

Patton adds, "He's already competitive, like an artist. He's like, 'I gotta song...!' He only writes choruses, no verses."

But he doesn't like performing with dad: "He says, 'No, no, no, it's my song... You got your song, I got my own song.'"

Proud Patton taped footage of her son performing during soundcheck at one of dad's shows and aired it during her appearance on Late Night with Jimmy Fallon on Tuesday (30Jul13).