Then those 2 kids that tried to kill them other 2 kids as there was "nowt better to do" get 7 years and will be out by the time they are 18 - probably just in time to actually kill someone next time!
No they won't. They got an indeterminate sentence, meaning they won't be released until they're deemed safe. Which given they've been assessed as bordeline psychos is likely to be a lot longer, possibly never. The 7 years is the minimum period before such an assessment will even be considered
