Ragnarok: Loki's Children
It's been years since the invasion of New York, the Convergence, and the Ultron Crisis, *Civil War doesn't happen* and the Avengers have all had kids, most of them teenagers now. They live somewhat normal lives, attending high school, as their parents fight global threats. Unknown to the Avengers, Loki has also settled down and has three monsterous children of his own: Fenris, an enormous wolf, Jormungand, a giant sea serpent, and Hela, a girl with a body that's half corpse. These children attend high school with the Avenger's children in human forms, unaware of their true nature. Loki intends on keeping it this way, but with the prophecy of the Ragnarok emerging he may have no choice but to unleash his children's inner nature.
*I don't own any of these characters, this is just fan fiction*