Twilight, Starlight, Cozy and their brother Jak, along with their friends Keira and Daxter, spend their days playing around the village, helping the other residents of Sandover whenever they can, working on their hobbies, and occasionally learning from Samos, the Green Sage that calls their village home, even though Daxter often gets him and the others in trouble whenever they do anything interesting. That doesn't stop them from having fun and learning a few skills to defend themselves, all while unaware of the grand adventure that they'll be embarking on in the near future, along with the fact that the fate of the world depends on their actions to come.
(Jak and Daxter/MLP crossover)
(Part of the Demon War story series, but reading the others isn't required)