Teaching your teenager how to drive is a nerve-wracking milestone for any parent.

But Bec and Lleyton Hewitt seemed to have things under control on Wednesday as they took their 17-year-old daughter Mia out for a spin in Sydney.

The couple secured L-plates to their brand-new $53,000 Mini Countryman with all three of their kids in tow, as Mia stepped into the driver's seat.

The vehicle, which featured sporty black detailing on the bonnet and leather seats, is believed to be Mia's car - possibly a birthday gift or reward for doing well in school.

Bec, who has been married to former world No. 1 tennis ace Lleyton for 17 years, wore a black tank top with baggy high-waisted pants.

The former Home and Away actress, 39, pulled her dark locks away from her face into a low bun.

Mia seemed a little nervous before jumping into the car, and her mum sported a look of concentration as they hit the road.

Before the Hewitts piled into the car, Lleyton was seen driving it to the curb as their younger kids Cruz, 14, and Ava, 12, excitedly checked out their new ride. 

Earlier this month, Bec and Lleyton were spotted enjoying a walk together in Sydney's Rose Bay.

At one point, they packed on the PDA as Lleyton leaned over and gave his wife a kiss on the cheek. 

The Hewitts have been married since 2005.

Following their nuptials, they relocated with their children to the island of Nassau in the Bahamas after purchasing a $3.8million villa in the Old Fort Bay estate.

In 2016, the family left the Bahamas and moved back to Australia. About year later, in April 2017, they purchased a home in Toorak, Melbourne.

The family then relocated to Sydney for Bec's appearance on Dancing with the Stars in what was originally supposed to be a temporary move.

Bec rose to fame playing Hayley Smith on Home and Away from 1998 to 2005. She also had a singing career, releasing the hit All Seats Taken in 2003.