April O'Neil is a fictional character in the Mirage Studios franchise Teenage Mutant Ninja Turtles. In each of the many TMNT continuities, she is a good friend of the Turtles: Leonardo, Raphael, Donatello and Michelangelo.
In the original Mirage Comics storyline, April, who originally sported a jumpsuit, was a skilled computer programmer and worked as an assistant for Baxter Stockman, helping to program his Mouser robots and demonstrating their operation. After she discovered that Baxter was using the Mousers to burrow into bank vault and steal from them, she attempted to flee Baxter's workshop and found herself in the sewers running for her life, with several Mousers in pursuit. Three of the Turtles happened to come across her and save her; they later successfully fended off a Mouser invasion after Baxter programmed them to attack the Turtles.
April began to run an antique shop, which came under attack by The Shredder and the Foot Clan (who had come for the Turtles), and was destroyed in the ensuing battle. She and the Turtles retreated to a farm house in Northampton, Massachusetts where she later had dreams about the Foot Clan's attack. During the mid-90s, April became romantically involved with Casey Jones and the two eventually adopted a child named Shadow.
In Volume 2 of the TMNT comics, April was attacked and injected by a huge robot controlled by Baxter Stockman's brain (apparently, Baxter having escaped capture, had placed his brain in the body of a robot and sought them out in order to get revenge on April). It wasn't revealed until Volume 4 that April was injected by nanobots that seemed to have caused sterility as well as nearly killing her from the inside. With the help of the Utroms, the turtles sent turtle versions of nanobots to stop Baxter's versions and saved April before they would reach her brainstem. Despite this, April remained sterile.
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