Huh? Why? Back when I was married, we had a funeral every time one of our pets died. Not some big affair with other people, of course, but just a small little ceremony for ourselves in our home or in the backyard where we buried the box.
Writing goodbyes on balloons and letting them go as you did can also be said to be a form of a funeral.
We also didn't have a body in either case - maybe an empty box felt strange? I don't know. I am also very into breaking from traditions.