Since 2015, Guarini has been starring as Lil' Sweet in Diet Dr Pepper television commercials, and web marketing.

Justin Guarini You may recognize him from his time singing on American Idol, from his role as 'Lil Sweet' on the Dr. Pepper commercials, or from your local grocery store aisles. That's because Justin Guarini, when he's not entertaining the world, lives right here in Bucks County with his wife and two sons.

Despite what seems like a pretty obvious Prince influence, Guarini contends the character is a general glam rocker who is not based on any single figure. Deustch also denies he's based on Prince. (Nobody is confusing him for Ziggy Stardust, though … and some commenters seem to think it actually is The Purple One.)

Justin Guarini Does the guy in the new Diet Dr Pepper commercial look familiar to you? Early American Idol fans, rejoice – it's none other than Justin Guarini. The 36-year-old singer and Broadway actor stars in the soda ad as "Lil' Sweet."

A theory often cited is that the drink was named after an actual doctor, one Charles T. Pepper of Rural Retreat, Virginia. Morrison may have named the drink after the doctor in gratitude for Pepper having given Morrison his first job.

Fred Kaseburg Currently, Pepper serves as AARP's first Love & Relationship Expert & Ambassador and teaches at the University of Washington in Seattle. She has two children, Cooper and Ryder, and recently got married to her husband, Fred Kaseburg.

Lil' Sweet is a character and mascot made by Keurig Dr Pepper and played by 2002 American Idol runner-up Justin Guarini.

“The idea was that when people wanted a Diet Dr Pepper, they would ring a little bell and go, 'Lil' Sweet,'” Lehr said, “and then a tiny butler would come in. He would be in a tuxedo and have a little serving tray with a Diet Dr Pepper on it.

Lil' Sweet is a character and mascot made by Keurig Dr Pepper and played by 2002 American Idol runner-up Justin Guarini.

Originally made in Morrison's Old Corner Drug Store in Waco, Texas, the drink's unique flavor was a hit when it was first sold in 1885. Wade Morrison, the drug store owner, named it "Dr. Pepper" after Dr. Charles Pepper, a Virginia doctor who was the father of a girl Morrison was once in love with.

Fan-favorite characters Logan, Jay, Natalie, Chuck, Charlotte, CJ, and “The Sheriff” Brian Bosworth are all back this year, joined by USC quarterback and Heisman trophy winner Caleb Williams and his mother, Dayna Price.

Guarini's was the runner-up in American Idol's first season. He has since released two studio albums, two EPs and has appeared on Broadway and television. Watch Guarini and Clarkson reminisce on their Idol experience above.