So what I can understand is that the kid is working under a superstition that if you take a peice from a tea set and bary it under the roots of a tree you can make a wish come true. The wish is the thing that's up for interpretation.
I belive the kids thinks his moms wish or his wish for his mom is for her to be happy. He knows that his mother is longing for her old love by barying the spoon I believe he thinks that will make her wish come true ( the wish being either for her love to come back or for her to be happy). When he shows him the spoon and he claims he doesn't know about her wish (her wish for him to come back as if saying he didn't come back because he wanted to come back to her but because it was "madatory") it proves to the kid that him barying the spoon did nothing and he throws it away.
Then at the end when the guy confesses his love and says he's sorry the spoon appears as if signifying that the wish did come true and that his mom is happy now. Also I think the kid chose two methods to make his mom happy one Killing her and then after she was dead since he couldn't confirm if she was happy he keeps trying and barys the spoon.
Hope that helped or made sense that's alot to read too I wonder if you'll read this since I'm 4 years later.
Can someone explain the significance of the spoon?