Josie Stronghold (AKA Jetstream) is Will's mother and the wife of Steve Stronghold (the Commander). She along with her husband are the world's greatest superheroes. 

Her superpower is supersonic flight. She is also an expert in the art of hand-to-hand combat.  Her breasts look increasingly delectable when wearing her superhero costume. This appearance advantage helps distract her enemies and makes combat easier for her.