Brad Pitt Takes Son Maddox Go Karting

Brad Pitt played doting dad on his son Maddox's 7th birthday Tuesday -- by spending a little one-on-one time go karting.

The Hollywood hunk -- whose partner Angelina Jolie gave birth their fifth and sixth children in July -- took Maddox to a go-kart race track near their $70 million French chateau.

There was no sight of Angelina or newborn twins Knox and Vivienne.

It's not the first time Brad, 44, and Maddox have shown their need for speed.

In June, Pitt took his son to the the Italian Grand Prix in Scarperia, Italy.

"Brad was really protective of Maddox," a witness told Us Weekly at the time. "Often, Maddox would tap Brad's leg so he could be lifted up, and Brad would always do it willingly."

Pitt and Jolie recently revealed that twins Knox and Vivienne have brought "wonderful chaos" to their ives.

"It is chaos but we are managing it and having a wonderful time," Angelina, 33, told Hello! magazine while Brad joked that their home was "still a cuckoo's nest".