Interesting alright, and while I agree with some of what's said, particularly the glorifying of him as an 'all round good guy', which is pure nonsense, for me, it's very simple. The man committed the murders, he gets the coverage. The children added in simply to sell newspapers and get people talking about it, because that's what most people connect to on a personal basis. I think it's simple psychology here.
Talking about the woman killed wouldn't attract as much attention, and not because she's a woman, but because she's a grown adult. People have become somewhat desensitised to these stories and it doesn't affect them on a personal level unless they've personal experience of such a case. Likewise, if it was the other way around, and the wife done this, I don't doubt for one second she'd be the one getting all the coverage. The infamous 'Scissor Sisters' being an example of this. The man brutally butchered in that case was barely discussed, and all the headlines were about the two women.
I don't think there's any underlying sexist issue here, but it suits some people to spin it like that.