I would highly recommend they seek professional help from an animal behaviorist. Dogs do not attack for "no reason", they attack for very specific reasons and "unknown" reasons are often labeled as "no reason".
Granted not all cases of "rage syndrome" are that many are simply behavioral problems that the owner do not know how to manage, But in cockers and english springe spaniel, "rage syndrome" there is demonstrable evidence of medical origins for the condition which are largely untreatable. There even appears to be a genetic link. Current belief is that it is quite possible a siezure disorder. That said there is not a know cure or control.Dogs do not attack for "no reason",
The results suggest a genetic and neuroendocrine basis for the differences in aggression. Dr Podberscek carried out a ‘cluster analysis’ (grouping together of aggression categories) which showed that there is some evidence that rage syndrome is an expression of social dominance, rather than being a separate or pathological phenomenon. There are 2 main theories as to what this syndrome might be:
a) An unusual form of dominance aggression
b) Type of epilepsy – might be part of a group known as complex partial seizures.
The study provided important information on the prevalence of different types of aggression in the Cocker Spaniel.
Conclusion
Although rage syndrome has been studied for a number of years, it cannot be accurately predicted and can only be diagnosed by EEG or genetic testing and these tests are not conclusive.