United Kingdom, May 4 -- Hilary Duff has said recent documentaries examining the darker side of child stardom have left her feeling "really quite sad".

The actress and singer, 38, defined a generation with Lizzie McGuire, made the remark as she reflected on her own early career.

Hilary rose to prominence in the early 2000s through Lizzie McGuire before expanding into film roles such as A Cinderella Story and a music career that included albums like Metamorphosis.

And speaking at the Time100 Summit in conversation with Dan Macsai, she addressed the renewed scrutiny on children's television prompted by recent releases including Quiet on Set: The Dark Side of Kids TV and Framing Britney Spears.

Reflecting on watching such material, Hilar...