Why wait? It's not a bad thing for kids to learn the circle of life, so to speak. Kids are quite resilient. If you are matter of fact about it and explain what is going to happen and why, they will be more likely to accept it. If you take care of it when they're gone, what are you going to tell them when they come home? The truth? Or lie to them and have them find out the truth later. Either way, will they wonder what's going to go next time they are gone? Maybe it's because we are farmers and my kids grew up with processing animals, but they were never traumatized by it.
When my boys were 10, 8 and 6, we got a little bull calf from a friend who was quitting milking. This was the last calf born on the farm. He was a week old. My boys named him Butch, "because we're gonna butcher him anyway, Mom". (I had a harder time than they did when it was time for Butch to go to the processor!)
Honestly, it's easy for people - especially the clueless ones on the sideline to criticize. I would tell them, "My chicken, my decision. You don't like it, he's yours."
