One Piece Saddest thing to happen *Spoilers*

What is the saddest thing to happen on One Piece?

To me, like I said spoilers, what happened to the Going Merry is the saddest. Going Merry is gone. She sank. :cries:

Merry was more then a ship. She was a part of their nakama. It has to be the saddest.

So what do you think is the saddest even though this is a fun loving anime/manga?