As the rest of the Fantastic Four mourn her, Reed puts their son on her chest to say goodbye, and then he miraculously resuscitates her. The parents spend most of the movie worried that Franklin might be some kind of monster like Galactus,

In a 1982 arc by John Byrne, Franklin gets frustrated trying to solve a Rubik’s Cube and uses his powers to age himself into an adult body, though he couldn’t actually gain more emotional maturity. He winds up going back to being a kid, placing restrictions on his own abilities to allow him to have something of a normal childhood.

This story discusses major plot developments, including the ending and post-credits scenes, in "The Fantastic Four: First Steps," currently playing in theaters. From the very first scene, the question of what will become of the child of Reed Richards (Pedro Pascal) and Sue Storm (Vanessa Kirby) looms over "The Fantastic Four: First Steps.

Franklin’s powers allowed him to create the universe, dimensions, avoid mind control, and every other cool power you can think of. Franklin Richards is considered a Beyond Omega Level mutant, and he is the only one in that category, making him the most powerful mutant on Earth.

Franklin Richards isn't just another superhero offspring; he's one of the most powerful characters ever created in the Marvel Universe.

First Steps introduces plenty of characters to the MCU, but its strongest one isn't Galactus or Franklin Richards.

In their MCU debut, the Fantastic Four become a Fantastic Five with the arrival of Reed and Sue's son, Franklin Richards. Worries that he might not be "normal" are confirmed in Fantastic Four: First Steps when Galactus recognises that the boy can wield an unlimited energy known as the Power Cosmic (presumably because of the "cosmically compromised DNA" shared by both of his parents).