My bunny died recently. (We were very sad.)
But I can't find the reason why.

It was around fall, when it was pretty cold out. She was eating fine and acting normal. Her stool were normal and healthy. We didn't change her diet or give her anything new. But her ears started to get colder and she started to get more calm. She got weaker and weaker and started eating less.

I insisted to take her to the vet to my sister, (the owner of the bunny), but she didn't.

Then after a few days, she died...

I don't know what could've caused her death and it's just so heartbreaking to me and my sister. We loved her very much and she was still young.

If only I found out what caused her death, I'd feel a little better.

That's sad... really sad. Not all answers are knowable.

Rabbits get hairballs but can't expell them like cats. I had a friend whose rabbit died because of this. I don't know what the solution is to this but if you look it up online you should be able to find an answer. So sorry for the loss of your beloved pet!

It sounds like she froze to death.

Sorry about your loss

It has to be pretty dang cold for a bunny to freeze to death. Still, this might depend on where you live. Was she being kept outside?

Ultimately, it's hard to say what killed your rabbit. It could have been a number of different things.