Alvor by Laura Bingham
Erin and her twin brother, Bain, never expected to find that the cabin in the woods near their home is actually a secret entrance to a magical world. Surrounded by pegasi, dragons, and fairies, they discover new powers within themselves and a secret they have unknowingly been preparing for: they are training to become elves. Now they are faced with the decision to stay in this dream world or return home to the life they knew. A spellbinding tale of fantasy and fairy tale, Älvor draws you into an enchanting world of all things magical.