I wanted to bring things back on topic after initially thinking it was a different property but those are my impressions after reading up on this property and viewing the trailers for both. Context is everything so I'll have to see it to really comment specifically but the fact that it was spun into a TV series makes me wonder what it had to offer compared to the movie as I didn't really like the movie trailer.
That scene she was pretending to cry and the lady was trying to comfort her and she lured her in to kill her methodically when perhaps could've escaped earlier the scene seemed to project. As far as stabbing goes, I think the act in and of itself (the type of knife, frequency, motion, placement are all factors to consider of course along with intent defensive or not) can be less brutal than cranking someones neck to break it. I think trying to break someone's neck is less quick and efficient generally speaking than slashing at someone but of course in the movies it's always super deft and quick and instant death as well. 100% probable no complications or paralysis afterwards I highly doubt it.
