Robert Downey Jr.'s 11-year-old son makes fun of his car skills in 'Downey's Dream Cars' trailer

Exton, Robert Downey Jr.'s son, is a surprise guest star on his new reality TV series. The first trailer for "Downey's Dream Cars"—the "Iron Man" actor's new reality TV series—was released on May 18 by HBO Max. The show will follow the celebrity as he attempts to restore six of his classic automobiles.

Downey Jr.'s 11-year-old son makes a memorable appearance in the trailer, creating more excitement for the upcoming series. Downey is known to have a quick wit and a good sense of humor. Exton seems to have gotten those exact genes from his father and has no qualms about using them against his old man. 

In the trailer, we see Downey Jr. using the food around them to demonstrate the work he's doing on his cars while the duo is eating lunch together. Exton uses this opportunity to make fun of his dad's car skills. Holding up a french fry, Downey tells Exton, "This is a clue you'll never guess." Without missing a beat, Exton wittily responds, "It's a biodiesel conversion." Later, as the actor brags about being a "gearhead" and a "grease monkey," his son turns to the camera and comments, "Are we sure he's the right guy to be hosting this show?"

Downey Jr. and his wife Susan Downey share a son, Exton, and a daughter, Avri. He also has a 23-year-old son with his ex-wife, Deborah Falconer. The actor is quite private about his children's lives. 

In April, he celebrated his 58th birthday with a sweet video featuring his children. He took to Instagram to share a montage of his 57th year, which began with him celebrating his 58th birthday with his wife Susan and his three children. "57, you've been too kind. With gratitude, I shall rewind," he captioned the video.

One could guess that one of his favorite memories from the year was when he let Avri and Exton shave his head before filming a project. "Sorry to interrupt but I need your help," Downey Jr. began the video while entering a room where his kids were carving pumpkins. "You know how I'm starting this project soon?" "Yeah, "The Sympathizer"?" said Avri, as Exton added, "Yeah, you're playing like five roles or something."

"Right. Well anyway, I don't want to wear a bald cap, so will you guys shave my head?" he asked his children, who looked at him baffled. "Is that even appropriate?" Avri questioned with a smirk on her face before she and her brother began shaving their dad's head. Downey Jr. also included several other memories of his 57th year in the recollection video.

The star shared the "Downey's Dream Cars" trailer on Instagram with the caption: "Have you ever had a weird dream? Where your entire family got involved, and joined you on a wild adventure of Discovery Plus Eco Mindedness? Did you meet Magical Creatures along the way, who surprised and delighted you with their Super Green Human abilities? Did you experience the Fantastical Future Of Mobility to the MAX? I’m just waking up, but I think it MAYBE ACTUALLY HAPPENED... Buckle up, this thing's got torque."