Jor-el is the father of kal-el (superman/Clark Kent). Mon-el was a traveler from another planet (daxam) who had the same powers as supes he crashed on earth after exposure to lead (his weakness) poisoned him. To save him superboy placed him in the phantom zone where he stayed until one of the legion of superheroes in the future created a serum to cure him. That hero was Brainiac V, who was a descendent of a slave of one of supermans greatest villains- The computer minded Brainiac. Hope that helps ;-p
Oh there is also zor-el, Kara-el (supergirl), and ....
There were also:
Di-Gel
Loop-El
Int-El
and
Rang-El