I don't think my hens woukld care if the roosters were gone. My first batch, now over a year and a half did fine without any roo's. This year I have four young roosters and I am sure the original three HATE them! LOL
And we have 4 because one I hadn't planned on keeping (derned McMuray's sending the extra rooster chicks), turned out to be such a cute friendly little chick. He is the king of the flock though, and very watchful. When selling off the pullets I didn't keep, my DH tried to calm him down. My idea was to just let him get over it and leave him be. But DH repeatedly tried to handle him while he was in a 'state' from having his girls caught up and handed over to strangers. Finally, Zorro went after him. Then he started attacking the DH whenever he came to the barn. DH threatened to kill him. I still like him, so as a last resort, I told DH to just 'move' Zorro out of his space, carefully but deliberately. I told him to move sideways, stepping his foot over first, to displace Zorro. It seems to have done the trick. Now Zorro leaves the DH alone. I hope it stays that way.
But if a 7 year old was involved, I feel there is no choice. I would rehome him.
*IF* you do stew him, I would not make the child feel responsible. I certainly wouldn't have her watch. That could do more mental damage than anything!