"My dad went and got all the videos from the basement and put them online, and I almost died when I saw them," she said. "I'm like, 'Daddy! I have braces and my hair is wing-backed!'"
In at least one video, DioGuardi is seen belting out "Hello, Dolly." She admitted to being a big fan of show tunes. "I used to sing 'Getting to Know You' to my grandfather," she said. "I mean, that's what I heard on Sundays -- Frank Sinatra, all the show tunes. That's what my parents loved. When rock music came on, I was, 'Shut that off, be quiet.'"
DioGuardi's early opinions on rock music may seem ironic, considering where her career has taken her since.
Before she began writing music, DioGuardi studied opera at Duke University -- for about a minute. "I was accepted, went there, went to one class and was like, 'No way. There's no way I'm doing that,'" she said, laughing.
She remembered thinking the Opera style wasn't a good fit. "It was just so bottled up and disciplined and 'Breathe like this, and sing like this, and act like this,'" she said. "It wasn't for me."
But it did help DioGuardi recognize what she did want. "When I graduated, I wanted to be an artist, and no one would give me their songs, and THAT'S when I became a songwriter," she said.
DioGuardi said the most important part of being a songwriter is being able to write about one's experiences, what she calls her "truth."
"I had to really start looking at that and be honest, and experience what I was feeling for the first time and really put it down on paper, she said.
As a recording artist, DioGuardi was signed for a brief time, but it didn't last long. She said at first the rejection was a hit to her self-esteem, and she worried something was wrong with her. "I just had no sense of who I was as an artist," she said. She could switch easily between pop, R&B, rock, or other music genres -- but it left her with no concept of who she was as an artist.
"I don't even know that I do now," she said, "I just know who I am as a person. There's a big difference."
A defining time for DioGuardi was during the seven-year battle her mother endured with ovarian cancer. She died when DioGuardi was 26. Although it was an emotional time for DioGuardi, the experience is one she draws on when writing emotionally-driven songs, like "Mama's Song" with Carrie Underwood or Pink's "Sober."
"It's all about what their truth is and what my truth is. For instance, half the time I don't even know them. We sit down, 'Hey nice to meet you,' I start asking questions: where are you from? What's your relationship like with your parents? Do you have a boyfriend? Have you had your heart broken?" And the more they talk the more I say, 'I totally understand that, I completely understand that.'"
"Sometimes it's uncomfortable because I'll see them out and we had this really revealing moment where they may have cried or said something they've never said before," she said, but DioGuardi knows that those are the types of experiences that produce great songs. She said that writing often leaves her vulnerable as well, but it's worth it.
"Why do that if you're not going to get right to that moment?" she said. "I feel like I'm always risking a part of myself when I get in that room, too, because I may reveal something and they may be like 'Oh God,' she said, laughing.