(If you want Godzilla Jr. from the series click Zilla Jr.)Godzilla Junior (ゴジラジュニア, 'Gojira Jyunia'), also known as Baby and Little One, is the biological son of Godzilla featured in the later movies of the Heisei Series. Miki Saegusa acted as a mother figure to him in the first film. He had the longest screen time for a kaiju in any Godzilla film for almost the entire film in Godzilla vs. Mechagodzilla II.
Baby Godzilla's (ベビーゴジラ, 'Bebii Gojira') first appearance was in the 1993 film Godzilla vs. MechaGodzilla II. Baby Godzilla's egg was found on Adona Island with a Rodan's egg. The Rodan egg hatched and looked after the unhatched egg. Godzilla himself looked to have interest in the egg. But Rodan fought Godzilla to protect the egg but failed. However, scientists took the egg during the fight. Godzilla then went to Japan to get the egg while Rodan woke up and turned into Fire Rodan and went to claim what was his. The egg hatched and much to the scientists surprise, it was an infant Godzilla and found out that it has a second brain in its ribs. This made the scientists know Godzilla must have a second brain as well. So they created a Mechagodzilla to kill Godzilla. But Rodan comes in his fire form to fight Mechagodzilla and fought well but failed. Godzilla fights Mechagodzilla and wins. But the scientists upgraded Mechagodzilla into Super Mechagodzilla and succeeds to destroying Godzilla's second brain. Godzilla seemed to have died but listening to Baby Godzilla's cry Fire Rodan gave up his life essence to Godzilla and disappears. A newly revived Godzilla destroys Mechagodzilla with his sprial ray. Baby Godzilla and his new father swim off to sea to find a new home.
In Godzilla vs. SpaceGodzilla, Baby Godzilla grew into Little Godzilla (リトルゴジラ, 'Ritoru Gojira') in his new home Birth Island. SpaceGodzilla trapped him in a crystal prison until his father Godzilla killed Spacegodzilla. Little Godzilla was also seen having the ability to breath radioactive "bubble" breath similar to minya's smoke rings. Little Godzilla is not anything like his father because he is not mature enough.
Godzilla Jr. In Godzilla Vs. Destroyer
Godzilla's melt-down was caused by massive underground deposits of uranium that were exposed somehow to Godzilla which ended up obliterating Birth Island entirely. Little Godzilla is missing and presumed dead after the explosion. He is finally found, much larger and a third the size of Godzilla and is now called Godzilla Junior. The JDF convinces Miki reluctantly to lure Godzilla Junior to Destroyer. Miki lured him to Destroyer so that Godzilla Junior would engage Destroyer in battle hopefully bringing Godzilla to the fight so Destroyer could stop Godzilla's melt-down.
Godzilla Junior soon finds Destroyer but is knocked down by the monster as Destroyer then utilizes it's inner jaws ripping into Godzilla Junior's chest causing much blood loss absorbing Godzilla Junior's blood and injecting micro-oxygen into his chest. Junior however, is able to blast Destroyer with his atomic ray at close range, sending Destroyer plummeting into a nearby building where it is soon engulfed in flames and is presumed killed. Godzilla arrives soon after and the two greet each other. However, Destroyer merges into it's final aggregate form, topples Godzilla and grabs Junior with his tail flying high above the airport dropping Junior onto the terminal and killing him.
Miki Saegusa and Godzilla are very heartbroken for the death of Godzilla Junior as Godzilla tries blowing life back into Junior with soft atomic breath desperately trying to revive Godzilla Junior who dies shortly thereafter. Miki is sad knowing that another kaiju will die soon himself: Godzilla. Godzilla succeeds in battling Destroyer to a standoff with the assistance of the JDF, who eventually turn their weapons on Destroyer after Godzilla unleashes his red spiral atomic heat ray, taking several shots knocking out large chunks of Destroyer's body apart. Destroyer soon flies into the air allowing the JDF to knock him out of the air with their freeze weapons killing him permanently. Godzilla afterwards begins melting down. The fallout radiation soon fills the skies of Tokyo turning it into a ghost city. The radiation however begins to disappear entirely and through the cloud of haze a larger form is seen moving around. Godzilla Junior has fully developed into an adult Godzilla and roars! Godzilla dies and is essentially reborn through Godzilla Junior, mutating him into an adult. Showing that Godzilla's legacy will continue on through the restored Godzilla Junior. Godzilla senior died as a kaiju but is reborn through his son as a God.