> some kind of ceremony

In hindsight, I think this is where we messed up. At the time it really was unclear how our daughter would process the death. If it were happening now, there's no question that we would have let her be more involved.

That said, I don't think she's struggling with closure. She just wants to look at pictures every so often and sometimes she says something that catches me off-guard emotionally.

Undisciplined

Dogs_And_Cats

Dealing with Dog Loss with a Little Kid

We recently had a smaller, non-dog/cat pet die suddenly. In the matter of a day it went from "something is odd here" to dead. It was really dramatic and was interesting to see our 8 year old immediately say "can we get another one???" , which I guess is a normal thing for kids to say. 

We had them say goodbye while they still could, then we did a funeral a few days later. The 8 year old went out to visit the grave the next day, but now it's been months and nobody has said much about it. 

If you haven't done some kind of ceremony, it might help bring some closure for the kids, and you. 