I will pray your friends dogs will all be ok. That guy should be poisoned if he was responsible. I too never leave my pups out unattended and I walk all around the yard looking for anything my loser neighbors could throw over the fence. They are druggies and we have had our problems. The mother has dogs and I doubt she would try anything, her daughter however is the devil himself. Teaching dogs the 'leave it' and 'give' commands are helpful also, if you do see them pick something up. Please keep us updated on how the dogs are doing.