can't remember?

I cannot remember what this is from, but I do recall that I loved hearing the different versions of this tale.

Basically this boy is sent by his village to get a cure for a disease. At one point he passes a dying willow tree that is next to a river, the tree asks him for help, but the boy ignores it. The same thing happens with two other creatures he meets. A poor girl from the same village heads out after him to help, much to the derision of the villagers. She helps the willow tree (finds a treasure chest are blocking the roots from the river) and the other creatures and then gets the cure. The villagers are shocked that someone so unpopular/ugly/poor had managed to save them all.

Any clue as to where this is from?