Yup the shutter speed there is too low for a sharp shot but I wouldn't be so quick to dismiss shots like this one. Photography is supposed to be an expressive art form and the camera is so much more than a tool for faithfully documenting what we see in front if us.
Now I don't know if the shot was supposed to come out like that but I suspect it wasn't as and such the shutter comments have to be made....
but lets stop and just consider that shot for a moment. We're stood up, we're on a beach and were all wrapped up in coat, scarf and hat..... We're out for a walk in middle of winter, blasting away the cobwebs and enjoying the majesty of the sea. At least that's what I'm taking from the shot. The expression on mums face is one of good natured tolerance. While not really wanting her photo taken she's willing to let this one pass as it's one of her brood.
The movement in the shot is evocative of being by the sea in the wintertime and helps to convey the feel of the wind and spray of the sea.
Not a bad haul of feeling and info passed over in less than a second of viewing a blurry snapshot eh?