Alex is half-human, half-alien and friend of Ben, Gwen and Kevin. Alex's mother is human, while her father is a Vaxasaurian (aka Humungousaur). When Alex's alien powers kicked in, her father gave her his plumber's badge so as to keep her safe and not be mistaken for an alien invader. Alex has known the gang since Ben first got the Omnitrix and they have been good friends ever since. Alex has a slight crush on Ben, but doesn't act on it, not wanting to ruin their friendship.