I have a feeling with a bit of practice she will have that joke down solid. I used to have one about a brick and another one about a frog at a bank and the set up definitely makes the joke. Given what my wife does, she usually has some pretty strong opinions about death and when the right time is to talk to kids about it and things. I can't tell you the specifics (in case you wanted to compare), I just know there have been times when she said (they shouldn't have taken the kids to this funeral or that funeral). Then there are times when she thinks it is totally okay, so I am guessing it is situation specific. I don't know, I just work on computers all day!
It depends on the child. If they have been raised to be fearful, or avoided death altogether like many I know, then they might not be ready for a funeral, and the parent not ready for the feelings and questions to follow. For me, death was just part of life. I think I was around Smallsteps' age when I went to my first funeral, for my mum's best friend who died of cancer. It was sad, but not bad.
I used to! ;D
I remember being little and having to be a pall bearer for some relative I hardly knew. It was honestly quite traumatizing, so I kind of get it.