Jessica Simpson's kids are giving James Corden's beloved Carpool Karaoke the cutest makeover.

While their pop star mom has veered away from the music scene to focus on her fashion empire in recent years, the "These Boots Are Made for Walkin'" songstress showed fans that her little ones definitely got their vocal chops from their mama, as they added a serious dose of adorable to a car ride singing session.

"..and he is 4," the proud mom of two captioned a clip on Instagram, which shows daughter, Maxwell, 5, and son, Ace, 4, singing "Happy Birthday" in honor of her son's special day. "#ACEKNUTE #carpoolkaraoke," she added.

In the video, the look-alike siblings officially melted our hearts as they shyly sang the jingle before flashing big smiles at their mom, who gave a big cheer at the end. Too cute!

The Dukes of Hazzard star also shared a sweet photo from her young son's birthday party that shows the ecstatic toddler with a white birthday cake, topped with a large "4" candle, and a bundle of colorful balloons.

"May wish #4 come true my beautiful baby boy," Simpson wrote.

Looks like the Simpson family started off their weekend on an adorable note, quite literally!