It's a bit odd, I'm not sure what they're trying to achieve? Is it supposed to look natural, like they went for a nice family walk then suddenly stopped and gazed adoringly into the children's eyes as they're such a loving, happy family? And there happened to be someone with a camera lurking in the bushes to snap the moment?! Thank goodness that even in such a spontaneous moment, the kids still had the wherewithal to hide their faces from the creepy stalker taking their picture...
Seriously, these weird photo shoots must be so confusing for them. If H&M really want to realise a public Christmas card for whatever reason, and they really don't want to show the children's faces, surely just have one of the two of them, or just blur the faces out. How are they explaining to the children that they need to pose at uncomfortable angles, or cover their face with their hair - I'd be pretty upset if my mum told me she wanted me to cover my face with my hair for the family photo! They just seem completely incapable of taking a nice normal photo where they look at the camera, it's always these weird, unnatural setups. I actually can't remember any of their own published pictures that haven't been oddly staged, and usually black and white. It's very dated.
But then, here we are talking about it, and that presumably is the point.