I am so sorry for your loss. R.I.P Fluffy.
You poor kids. They should recover quite well though. I agree about talking it out with them. The buriel was a great idea too.
You could tell your son Fluffy will be looking down on him from heaven and will be supporting him on his first day of big school. I hope it goes well for him, it is pretty scary.
Condolences to you all
