Looking for a passage in our youth that will eventually pass away

She forgot if it was Ruan Ruan or Zheng Wei who said that. It was the toy that she loved when she was young. She would hug it when she slept, but it disappeared later… What was that saying? I'll roughly say this sentence, please give me the original words! I remember that when I was young, I had a beloved toy. I cried and shouted for it from my neighbor's auntie. I even wrapped it tightly when I slept, afraid that it would disappear, but it still disappeared in the end... I found it many years later during a spring cleaning... I remember seeing it in the classic quote of our youth that will eventually pass away, but I couldn't find it. I don't remember under what circumstances Zheng Wei or Ruan Ruan said it