'American Idol' alum Justin Guarini on how he became Diet Dr. Pepper’s Lil' Sweet

Fans of American Idol may recognize Lil’ Sweet, the zazzy little—very little—star of Diet Dr. Pepper’s new campaign, as season 1 runner-up Justin Guarini. But how did it all happen?

Guarini called up EW to tell the story.

Have your kids seen your commercial? Do they realize it’s you?

The funny thing is, that type of humor and that type of behavior, I do it around the house all day every day. I remember saying during the shoot, “I can’t believe you guys are paying me to do this,” because that’s the kind of stuff I do for my kids and my wife – make them laugh.

Do you get Diet Dr. Pepper for life now?

[Laughs] Yeah, I’ve got it in my will.

Will we be seeing Lil’ Sweet in any more commercials?