Chiitan

Chiitan is a robotic baby. He was built by Hiroshi Ochanomizu and becomes Astro's youngest brother. He appears exclusively in the 1963 anime and some manga chapters. His name means "titanium" in Japanese.

Appearance
Chiitan is roughly the size of a human infant. He is built with similar features as his siblings, specifically pointed black hair: he has one point on the back of his head. Chiitan is still learning to walk, and so he crawls much like a human baby. He wears onesie suits with long thick sleeves.

An adaptation of Chiitan appears in Jetter Mars as the titular character's brother, Melchi.

Personality
Chiitan was created to be a comic relief character, giving Cobalt a break from being the comic relief in so many stories. Chiitan has a tendency to be rambunctious for a baby, and can act fierce if he doesn't get his way. He has some super strength, and is able to cry at extremely high volumes. At times, his bawling is loud enough to shatter glass and cause tremors.

1963 Anime
Chiitan appears mostly in the final season of the 1963 anime series. He makes his debut in the episode "A Great Fuss Over Babies". In this episode, the king and queen of Family Kingdom are distressed about not being able to have a baby. They decide to host a special competition for robot babies, through which they'll adopt whichever baby wins. Dr. Ochanomizu enters the contest and builds Chiitan. Unfortunately, Dr. Ochanomizu lets Uran see this robot baby, and she becomes very attached to him. With hopes that Chiitan loses and returns home with Ochanomizu and Uran, she tries to sabotage Chiitan's chances of winning the competition. Meanwhile, one of the other contestants abducts all the other robot babies in hopes their baby will win by default. Uran attempts to attract attention to the babies once she finds them, and Astro Boy hears this. Once Astro rescues the babies, the contest finally begins. However, while the queen bends down toward another baby, Chiitan crawls over and pinches the queen's bottom.

Uran is elated, thinking that the queen would never choose Chiitan after he pinched her, but the queen actually chooses Chiitan anyway. Uran throws a tantrum over this. The queen realizes then just how much Chiitan means to Uran, so she decides to give Chiitan to Uran, saying she couldn't bear to deprive Uran's family of a baby brother.

Manga
In 1966, Chitan appeared in a chapter of the same name in the Mighty Atom Club Magazine. In this version, Ochanomizu gives Chiitan to Astro and Uran as a present. Ochanomizu tries to teach the kids how to properly and safely handle a baby, but Chiitan turns out to have powers of his own and goes out of control.