Overview
Dashiell "Dash" Robert Parr is a fictional character who appears in Pixar's computer-animated superhero film The Incredibles (2004) and its sequel Incredibles 2 (2018). The character is voiced by Spencer Fox in the first film and Huckleberry Milner in the second film. Restless, relentless and curious, Dash sports a hearty sense of adventure and a boundless supply of energy. Born with the remarkable power of superhuman speed, he longs to be free to use his powers at his leisure, and chafes against the admonishment by his parents, in particular his mother, that his powers must be kept a secret.
Development
When designing the Parrs, Brad Bird wanted each of their superpowers to be related to their personality. Observing that 10-year-old boys are prone to hyperactivity, he conceived Dash as "the average 10-year-old boy that can move twice as fast as anybody else".
The filmmakers cast rising eleven-year-old Spencer Fox who made his feature film debut in the 2004 film The Incredibles to voice the diminutive and mischievous son of Bob and Helen Parr. Brad Bird wanted to give Dash a realistic out-of-breath voice in certain scenes such as the jungle scene so he made Fox run four laps around the Pixar studio until he got tired. Due to Fox's voice maturing he was replaced by 10-year-old newcomer Huckleberry Milner in the sequel.
Producer John Walker said of Dash in the sequel, "Dash got a taste of life as a crime fighter in the first film. Returning to regular life doesn't really interest him—he loved fighting crime with his family and, even better, showing off just how fast he can be."
From Wikipedia (CC BY-SA 4.0).