It could have been worse, sure.
This is a story of a woman who dies and her older daughter. The story runs on two timelines, where we see the mother and also the daughter after the death of the mother. Both stories go around motherhood, set in a "traditional", or patriarchal social system, and how women who yearned for it end up feeling suffocated by it, and feeling guilty for not finding the "greatest joy for women" in motherhood.
In that sense, the story is interesting.
The part that kills the story is when the author starts over using the phrase "the key to your happiness is in your hands". You know, the title of the book (The Key), and the story about a key, and the secrets in the life of the mother... And when the author goes on and on, twice per page using THAT phrase, one can't help but wonder what was the editor doing or if this was more like a self-published book that never got ran through a beta reader that would have caught the overkill. (One mention in the end would have been enough, though if the reader needs to be reminded of it, either the author thinks the story is bad and doesn't land, or expects the reader to be stupid).
The book is pretty, the story is nice (though by the end, with actions between Beata and her father, regarding Zsolt, or the unnecesary secretiveness of Kati, regarding Zsolt and the key, are irksome, to say the least), but really, the overkill with the phrase spoils what could have been a four star book.