Status: One-Shot Character First Appearance: "Raising Gazorpazorp" Voice Actor: Finnegan Perry (Baby Morty Jr), Will Jennings (Child Morty Jr), Richard Christy (Teenage Morty Jr), Maurice LaMarche (Adult Morty Jr)
Morty is a teenage boy and teenage boys have needs, so when he spots a lone sex robot draped to the side in an alien pawn shop, he nervously asks Rick to buy it for him. Rick indulges his grandson and purchases the doll, leaving Morty to freely release his energy into, much to the discomfort of the Smith family.
Unfortunately Morty bit more than he could chew; the robot rolls up into a ball and squirts out a half Gazorpian, half human hybrid. It turns out the robot was an incubation machine built by the female Gazorpians for their aggressive male counterparts to mate with. The fetus would be carried inside until its birth. Morty just became a teenage parent. Realizing he's a father now, Morty takes responibility for the child (instead of Rick's idea of brutally murdering it) and names him Morty Jr.
Because of the Gazorpians' unique nature, they are able to grow at an accelerated rate. In the course of a day, Junior grows from child to adult. This puts a dent on Morty's already poor parenting, further hindered by Beth and Jerry clashing with each other as they try to give Morty advice from their own experience. When Junior ages to toddler, he displays a dangerous need to destroy anything in his path because male Gazorpians are drawn to acts of violence. In an effort to keep both his son and the town safe, Morty lies to Junior to keep him forever locked in the house, saying the air is poisonous for him.
This takes a toll when Junior reaches his teenage years. He actively rebels against his father, smoking and lounging around in frustration. It's only when a heated argument ends with Morty pushing his son (a bare reaction due to Junior's massive girth) that Junior gets fed up and storms out of the house. Realizing there is no poison and his father had lied to him his entire life, Junior madly runs off. Faced with an unknown abundance of freedom, Junior literally dances until he's revved up, then starts smashing the town.
Once Morty finds his son, he calms Junior down by reminding him of his childhood. Junior admits he's confused, unsure of what to do with his life and how to express his anger. Suddenly, Brad Anderson, creator of the newspaper comic strip Marmaduke, appears to tell Junior to take his aggression and use it as a creative outlet. Taking the advice to heart, Junior bids his dad farewell to get a place of his own.
The next time we see Junior, he is a middle-aged man with a published autobiographical novel detailing his harsh condition living with his father. As embarrassing as it is for him, Morty merely hopes his son is taking care of himself.