Murder is premeditated, IE, he called her a Lesbian on the phone, she mulled it over, went downstairs, grabbed a knife, went to his place, got herself invited in then stabbed him, then ran off.
Manslaughter would be killing largely without premeditation, and I assume her being drunk might be being taken into consideration, but also, that together the two acts separately, because they both combined two separate acts to kill him.
If she stabbed him in the same way, at a pub, and got medical help, he wouldn't have died and she'd be done for attempted manslaughter or something else, likewise if he wasn't stabbed, not calling an ambulance wouldn't have done anything.
Its slightly more complex in terms of the law than, he stabbed him in the heart and he died in minutes, or commited a premeditated act.
Personally I think the stabber should have gotten a hugely worse sentence, and the sister who wouldn't call an ambulance should have been found guilty of some kind of torture or something, pathetic excuse of a rat bag, infact I think what she did was worse.
The first drunk sister was angry and did something violent but incredibly stupid, she panicked and ran, she didn't stab him 42 times, or make sure he was dead, she was drunk and reacted like a very stupid drunk person.
THe other sister wasn't panicking, was there, watching him die, and refused to do anything, its more malicious than the stabbing if you ask me.
The judge is likely inbetween a rock and a hard place, what sentence is standard for spur of the moment stabbings that aren't fatal in and of themselves, certainly less than a sentence for murder. What sentence to give to someone who refuses to call an ambulance, who even knows, the judge probably hasn't seen a case like that before.
Wasn't there a thread about the guy no one called an ambulance for in the states, though that was a case of too many people and everyone thinking someone else did it, and a big discussion about the good samaritan laws in lots of countries, where you would get put in jail basically for refusing to help, and we're one of a few western countries without such a law.