The granddaughter of Tony Stark is one of Marvel's biggest missed opportunities, as Iron Man 3030's single appearance remains an extremely memorable moment that begs for her future return. In Avengers #24, Rhodey Stark arrives from the future with the warning of a planet about to collide with Earth. Ultimately, she helps the Avengers stop the threat, but from that point on, Marvel never shows the hero again.
Tony Stark is no stranger to running into his extended family in the pages of Marvel Comics. After all, he's tangled with his brother Arno Stark while also battling his cousin, Morgan. When looking into the Multiverse, many alternate versions of Iron Man exist, including Antonio Stark in the Ultimate Universe, Natasha Stark aka the Iron Woman from Earth-3490, and Tony's sister Antoinette Stark's Iron Maiden of Earth-2301. Stark also has children and grandchildren in different realities, but few were as interesting as Rhodey Stark, a hero who made a significant impact despite making a single appearance.
In Avengers #24 by Jonathan Hickman, Esad Ribic, Salvador Larroca, Mike Deodato, Butch Guice, Dean White, Frank Martin, Paul Mounts, Laura Martin, and VC's Cory Petit, readers are introduced to an Iron Man from the year 3030. In the story, Iron Man 3030 sends themselves back through time - albeit not far back enough (noting there's still a version of Hyperion) - to warn the Avengers and Iron Man about an Earth-destroying event. Iron Man 3030 reveals someone from the future knocked a rogue planet out of orbit and that it's traveling through a straight line to Earth. Iron Man 3030 works with the Avengers to merge the planet with Earth while revealing herself to be Rhodey Stark, Iron Man's granddaughter from the future.
Rhodey Stark gives Iron Man key information that the merged rogue planet will be a powerful source of energy and a potential weapon if needed - teasing the events of Secret Wars. However, she also warns him of what's to come, telling Tony Stark that soon everyone will soon want to kill him, hinting at his fallout with the Avengers and the Incursions to come.
Marvel never revealed whether Rhodey is the actual biological granddaughter of Tony Stark or whether she was raised by him after something happened to War Machine and his future son/daughter. Regardless, Rhodey Stark's backstory begs to be explored further in future storylines, as her time in 3030, while briefly shown, is incredibly intriguing as she works alongside Franklin Richards in a desolate-looking future. She claims to be smarter than Tony from the present and quickly shows off her intellect in helping build a device powerful enough to merge the rogue planet with Earth. It would be fun to see what else Rhodey is capable of and how much smarter she really is than her grandfather - while readers could learn about her true parentage. Plus, her own Iron Man armor looks great and it's a shame it's never been seen again in action.
With the Multiverse being used as a plot device more than ever before, it's not out of the question that Iron Man 3030 makes a return in a future comic. It would be a welcome sight, as Tony Stark's granddaughter proved to be a worthy descendent of the genius-level hero, as her own smarts and technological innovations helped save a timeline she didn't even exist in. Marvel Comics would be foolish to never bring back Iron Man's granddaughter someday, as there are so many stories they could tell with her.