He has a rebellious son, Artie Smarty, who seems to be a real brat, but is an excellent skateboarder and also likes animals (in particular otters and Rufus).
He is the hero of Ron Stoppable, who has read his book three different times, without it ever being assigned.
In the episode "The Big Job", it is discovered that he is one of the richest five people on the planet. He was kidnapped, without knowing that he was kidnapped, along with the other 4 world's wealthiest people, when Senor Senior Jr enlisted Shego's help in order to pull off a successfully executed Evil Plot for his father's birthday, but was rescued by Ron and Kim.
He gave Ron a job in the Pet Department at Smarty Mart, located in Middleton, as a reward for saving him.