Our fish died when Greyson was 2 and a half during naptime and we waited until the kids woke up to be able to talk to Grey about death for the first time that he'd be able to understand.
Me: Grey, honey, we have to tell you something.
Grey: Okay, Mummie.
Me: Daddy's fish have died.
(show's Grey the dead fish in an empty bowl)
Me: You see how they aren't in the water anymore. They won't be living in our fish tank now.
I rub the side of his head and scratch his back lovingly.
Me: We are going to bury them* so they can go to heaven. That's where God and Jesus live, so we can pray when we want to talk to them too.
Grey continues to stare silently at the fish in the bowl.
Me: It's a little sad because they were part of our family and we'll miss them but they made us happy and we can still talk about and remember them.
Grey continues to stare silently at the fish.
Me: Honey, do you want to ask us anything?
Grey (with an excited look in his eye and mischievous grin on his face): Mum, touch his eye!
Grey: What? He won't bite you, he's dead.
*because these fish were 7 years old, they were so big that we literally could not flush them. We really did bury them.