First, the radiation somehow affected Susan Richards' body in such a way as to give her serious difficulties in giving birth. For unknown reasons, soon before she was to give birth to Franklin, Susan Richards' blood cells were observed to be carrying a strange form of energy that threatened the lives of both herself and the baby. Presumably, this energy effect is linked with Susan Richards' superhuman powers over energy that enable her to become invisible and to create force fields.
With Franklin's birth imminent, Reed Richards and his teammates, the Human Torch and the Thing, journeyed into the anti-matter dimension called the Negative Zone to find the only means known to Mister Fantastic of saving his wife and unborn son: the Cosmic Control Rod wielded by Annihilus, one of its most dangerous inhabitants. Mister Fantastic succeeded in obtaining the Rod and drained energy from it into a special container, which he and his two colleagues then brought to their own dimension. Reed Richards succeeded in using the energy from the Rod in bringing the energy in his wife's blood under control, and she safely gave birth to a healthy son. The infant was named Franklin Benjamin Richards in honor of his late grandfather, Franklin Storm, and the Richards' best friend, Benjamin J. Grimm. In his early years the sorceress Agatha Harkness acted as Franklin's nanny and protector.
The cosmic radiation that had given Reed and Susan Richards their superhuman powers also resulted in affecting the genetic structure of their son: Franklin was born a mutant. Unlike most superhuman mutants, whose unusual powers do not emerge until the mutant reaches puberty, Franklin began manifesting his superhuman powers at a very early age. The very first indication of his powers was shown when the Frightful Four had beaten the Fantastic Four, as a toddler Franklin Richards used this power to wake up the Thing and this allowed the Fantastic Four to achieve victory. In the normal course of events, Franklin's psionic powers would presumably increasingly emerge as he grew older until they reach their full, vast potential when he achieved maturity. However, this normal process was ruined by Annihilus, who, during a later conflict with the Fantastic Four, placed Franklin within a machine that triggered the release of his full psionic potential. Franklin was too young and inexperienced to control the vast energies building up within him, and Reed Richards feared that his son would be unable to prevent himself from releasing enough psionic energy to destroy all life on Earth. Unable to find another means of dealing with the problem in the short space of time left before disaster would strike, Reed was forced to use a device that rendered Franklin comatose, and thus unable to project psionic energy.
Months later, while the robot Ultron-7 was attacking the Fantastic Four and other superhuman beings, energy radiating from the robot affected Franklin's mind and caused him to unwittingly release great psionic energies which overpowered and defeated Ultron. Franklin was thus awakened from his coma, and his psionic powers were apparently now back at the level at which they were before Annihilus subjected him to his machine.
Later, Franklin used his powers to age himself into adulthood within a very brief space of time. (In this form he became known as Avatar.) Although his psyche remained that of a child, Franklin could now make full use of his psionic potential. Realizing he still lacked the emotional maturity to control his vast powers, Franklin transformed himself back into a child, imposing psychic "dampers" in his mind so he could not use his full powers until he achieved the necessary psychological maturity.
When the symbiote escaped from the Baxter Building with the help of Kristoff Vernard, the symbiote tried to possess Franklin, but Franklin was able to reject the symbiote thanks to his father and Spider-Man's help.
However, Franklin manifested the power to foresee events from alternate futures in his dreams. Unknown to his parents, Franklin became a member of Power Pack, a team of children possessing superhuman powers. He then took the "superhero" name Tattletale due to his ability to foresee the future. In one adventure involving Power Pack, Franklin even journeyed through outer space to the throne world of the alien Snarks and back to Earth. Franklin's "dream" power has also continued to evolve in other ways.
Later, claiming that Franklin's presence in this timeline would lead to destruction, Reed Richards' father Nathaniel abducted the child into the future. (In fact, Nathaniel had learned about the Fantastic Four's forthcoming disappearance upon defeating Onslaught, although he did not know about Onslaught himself.) Nathaniel raised Franklin for years in the future, training him to be a warrior and to master his superhuman powers. The adolescent Franklin journeyed back in time, arriving in the Fantastic Four's headquarters mere moments after Nathaniel had abducted him as a child. The teenage Franklin called himself Psi-Lord, and wielded vast psionic powers, although they remained far short of his full potential. For a long period Reed Richards was held captive by an enemy known as Hyperstorm. During this period, Franklin founded the Fantastic Force, a new superhero team to carry on his father's work of protecting humanity. Finally, however, Psi-Lord somehow was removed from the Fantastic Four's time and was replaced by the child Franklin, as he had been at the time that Nathaniel had abducted him. Nathaniel claimed that Hyperstorm must have arranged the substitution, and that the Psi-Lord version of Franklin no longer existed in the Fantastic Four's timeline. Ironically, according to Nathaniel Richards, Hyperstorm is the son of the Franklin Richards and Rachel Summers of yet another alternate future. […] -Marvel Fandom
