If you can say that something is both sweet and bittersweet at the same time, it would be the picture book, The Hole by Lindsay Bonilla and illustrated by Brizida Magro. It is due in February 2025 and I read via an online reader copy. But it might have to stay a one time read as it is not a happy story, but so tenderly done.
The loss of the brother in this story is handled with care and empathy. The overall tone is modern with how the emotions of the surviving brother are handled. This other brother is the narrator as well. The illustrations, while conveying the sadness, also keep things bright and hopeful. How the brother has passed is left open, allowing the reader to fill in the blanks as needed. Kid friendly and does not make things childish. It could even be given to an adult who has lost a child, especially one who had other siblings.
To try and lighten the mood, I will talk about the illustrations. The cover gives you a nice preview of things. Even when the family is sad, or the hole that follows our narrator around, is there, things are still bright. But there are a lot of colors and images that are positive, too. Not only does this keep things from being too gloomy, it shows the realistic idea of how things keep on going, they do not change just because loss has happened. We also see the community of slightly diverse people, the main character’s friend is a girl of color who seems mature for the physical looking age they are, but also realistic. It could work for several ages, but as the characters look about five to nine, I would not go much older or younger than that.