A movie about kids (boy and girl) becoming a friends and creating an imaginary world, and 1 day the girl dies, she tried to cross the river when it was flooding, boy went out with older lady to musieum and didn’t tell her, because he wanted to get away from her for a while.

I can’t add much more than that, but movie was made before 2009, and i’ve been searching for it for a decade :/

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