Songfacts®:

• Many toddlers were entranced by the TV series Doc McStuffins, which ran on Disney Junior from 2012-2018. The show is about a young girl is a doctor for toys, which come alive in her presence. Parents of these toddlers can often recite the very catchy theme song from heart: "Doo, Doo, Doo, you know what's good for you..."
  
  The song is also known as "The Doc Is In."
• The song was written by Kay Hanley, Michelle Lewis, and Dan Petty. Hanley was a rocker in the '90s, fronting the band Letters To Cleo ("Here And Now"). When she moved from Boston to Los Angeles in 2003, her friend Nina Gordon of Veruca Salt connected her with Lewis, a fellow songwriter an musician. They started writing songs together and came up with two show ideas they pitched to Disney, which got some nibbles but didn't go into development. In 2010, one of their contacts at Disney put them in touch with Chris Nee, who was looking for music for her new show, Doc McStuffins. Nee loved what they had to offer and signed them on to compose music for the show, which they did throughout its run.
  
  For the theme song, they collaborated with Petty, who also worked on the shows DC Superhero Girls and Sydney To The Max.
• For the first three seasons of Doc McStuffins, the theme song was sung by China Anne McClain, who was part of the Disney universe playing Chyna Parks on the series A.N.T. Farm. She later appeared in the second and third Descendants movies.
  
  The last two seasons, the theme song changed a bit as Doc went to work for a toy hospital. These seasons, it was sung by Amber Riley, who starred on the series Glee as Mercedes Jones.
• In addition to her work with Letters To Cleo, Kay Hanley also records as a solo artist, writing songs that can be very personal. In a Songfacts interview with Hanley, she talked about the mindset for writing songs aimed at kids.
  
  "When it comes to writing for animation, I'm literally writing a character," she said. "It's not about me. It's always in the service of a story, someone else's story, and that frees me up creatively in a way that allows me to have a truly, purely creative experience where I don't have any of the fears that plague me when I'm writing for myself."