Don and his older twin sister Dawn were born in the 30th century. Don, like his sister, inherited his father Barry Allen's superspeed. Although the 30th century was full of fear and hatred towards metahumans, the twins used their superspeed as superheroes. To hide their identities, they spun in circles at incredible speed, giving them the appearance of tornadoes. Together, they were known as the Tornado Twins.
Don married Meloni Thawne and fathered Bart Allen, who became known variously as Impulse, Kid Flash, and the Flash. Meloni's father, Earth's president, worked with the Dominators in an attempt to invade Earth. Fighting alongside the Legion of Super-Heroes, The Tornado Twins gave their lives in a successful effort to stop the Dominators' invasion.