The Summer Book by Tove Jansson

I cannot rave enough about this book. I finished it in July and I find myself wishing I could experience it all over again for the first time.
A little girl, having just recently lost her mother, spends the summer on an island with her father and grandmother. It's told in episodes. They find and foster a cat. Another little girl comes to visit. A man brings them fireworks for midsummer. There's exploration of the different parts of the island. Her father starts a garden.
What's brilliant about this book is the way the girl, Sophia, who is about six, works through her grief in her interactions with the world and others. There is only one brief mention of the mother's death but the sadness and bewilderment and rage and loss comes through in what Sophia focuses on and how she relates to the rest of the world. She can become terribly angry at things for no real reason. She suddenly has a need to build an entire imaginary world out of driftwood and stones and becomes deeply upset and scared that a storm might have washed them away. Her father goes out during a storm and her quiet dread is palpable.
The biggest relationship is with her grandmother though. They explore together, argue, build a town. She relies on her grandmother for advice and then challenges it. Her grandmother is clearly trying to do her best to help her granddaughter through a quiet, empty time filled with little understood emotions but she herself knows that her time is passing. There are important things she wants to pass on but she can no longer remember how to say them. She has little energy although she does her best to keep up.
There's a light that shines through this book. Everything ends eventually. But everything continues as well and there's so much out there to explore.