SOLVED. Children's Fantasy novel about two brothers that die and go to a different world. [s]

[Polde]

Around seven years ago I have read a children's book with some very deep themes about two brothers. They lived alone, their mother was dead. The younger was diagnosed with some sort of an illness and was dying but then suddenly the older one dies before him in some sort of an accident. When the younger one dies he goes to a different world where the older brother greets him. That world is similar to the one they were in before just a bit different and somewhat mystical, but still can't find their mother there. He spent some time there mostly exploring and gardening. I don't know exactly what happens next, but they die again and reappear in another similar world. Events seem to take place late 19th century, but there are little cultural clues about the time and place this is happening at. Everything is kind of mystical and I believe confusion of the reader and the characters is a big part of the story. I also remember an illustration of the two brothers climbing on a tree near a river if that helps.

[Becca]

The Brothers Lionheart by Astrid Lindgren, perhaps?

[Polde]

Becca wrote: "The Brothers Lionheart by Astrid Lindgren, perhaps?"
Yes, I am pretty sure thats the one! Thank you.