You receive a pony. You are uneducated in caring for it. The pony spends its life with limited contact in a small enclosure. It becomes psychologically traumatised, unsociable and unpredictable, but ultimately helpless, before dying of malnourishment at a young age. You grow up slowly realising all the things you did wrong, all the things you interpreted as love and contentment that were actually misery, bitterly regretting your childhood and constantly second-guessing yourself over whether what you're doing now is the right thing.

I wish that this wish will not be granted.