Natasha Irons was John Henry Irons' niece.
History
Natasha had a close relationship with her uncle John. She expressed disappointment at the fact that he could not spend more time with the family due to his desire to perfect the battle armor he was working on. She was with her uncle at his lab when Metallo and Intergang robbed a bank in their neighborhood. In the ensuing battle, Superman was exposed to a massive dose of Kryptonite radiation. John and Natasha raced to save Superman who was about to be killed. With Natasha at the wheel of John's van, the pair raced to Superman's aid. John managed to save Superman using a prototype battle gauntlet and get him into the van while Natasha did some evasive driving to escape the pursuing Intergang agents. John complimented Natasha's driving and the two got Superman to safety where John exposed him to a yellow sun lamp to recharge his powers. While he went out to hold off Metallo, he ordered Natasha to stay with Superman.
Background information
In the comics, Natasha also had an armor, and became Steel like her uncle. In the Justice League Unlimited comic, Natasha also gained this armor. In the animated short Justice League: The First Mission a cyborg girl is seen as a member of the Justice League. Some fans believe this girl is Natasha but no one has claimed this fact to be true.