Heretic

When Elizabeth finds a green-tinged creature in the woods she's amazed to discover that it's actually a girl of her own age. Isabella has spent the last 300 years in the faery world, hiding from persecutors who accused her of being the daughter of a witch. Elizabeth has her own persecutors to face. A catholic priest is hiding in her home - an act of treason in 1586 - and the net is closing in. As they become friends, Elizabeth and Isabella must find a way to protect the family from being torn apart