Sorry Garmama, that really sucks. I can relate though, I was babysitting my sisters 2 girls a while back and one decided she was going to help me clean up by useing soap to clean the fish
"but sponge bob uses soap?". She was more upset by the dead fish than I was so I turned it into a learning exp for her and she has "Her" aquarium now.....its gawd awful tacky but she loves it. Now she is the only 3rd grader I know who can explain the nitrogen cycle. Maybe you could use your ordeal to educate/bond with the little one?