"What I love the most about "Son Of Godzilla" is how it evolves the character Godzilla, by actually giving him a character. Before this film, Godzilla was just a monster - a living atomic bomb that could not be stopped and would fight any other monster that got in his way. But now, he has another life to worry about besides his own. And he intends to make his kid into another version of him, a cold, uncaring, unstoppable creäture of destruction.
But over the course of the film, even Godzilla begins to realize that Minya is not like him. Minya doesn't want to destroy other living beings, as he seems to avoid fighting Kamacuras, and wants to make friends with the humans on the island.
Suddenly, Godzilla has to stop being a monster, and become a mentor. One of the best scenes in the film is when Godzilla has to teach Minya how to properly roar and use his atomic breath. After Minya lets out a loud shriek, rather than his usual donkey-like noises, Godzilla nods in possible approval, but I don't think even he is sure what to think.
The same theme is shown in Godzilla. He is not just one creäture now, but the example for future Godzilla's'. He has to sacrifice his own needs and desires, so that his race can survive passed himself.
All of this culminates in the ending, which I hold as the best ending in the Godzilla franchise. After defeating a giant spider, Kumonga, that nearly killed Minya, a massive snowstorm has fallen upon the island. With the temperature dropping rapidly, it is becoming too cold for anything to survive. Godzilla has enough strength to leave the island, but Minya is too weak, as he stumbles in the snow, reaching for Godzilla's help.