Would you kill your grandma cause the made tea and burned the kids mouth? Yup here they might.
I get it but this goes too far. Maybe the family could maybe they even did, have offered to pay for the chickens and helped clean up, but I doubt it would have made any difference to the owner of these birds.
We have a cat, if I let him out of the house he would probably kill everything smaller than him, except kittens of course, he's terribly afraid of kittens, go figure, dude is huge weights like 22lbs and he's like 23 inches long minus the tail, but he's afraid of kittens.
So how bout we let this family pet live!!!!!!!!!