It is entirely possible for people to be in a blind spot while driving forward as well.

A few months ago I was driving into work and heading through a fairly busy part of town in terms of foot traffic. I slowed down to below the speed limit so I could focus better because there are a few sidewalks in the middle of turns in the road making it hard to see. Despite my best efforts I failed to yield to a mother pushing a baby stroller across a 4 lane wide section of the road. I managed to see her at the last minute and slammed on the brakes but I still slid halfway into the crosswalk while swerving.

If she had failed to notice me I probably would have clipped the stroller. It would have been at fairly slow speeds(maybe around 5mph) but the kid would have been taken to the hospital and it is possible I could have caused some serious harm. The issue arose from my perspective because she was wearing all black, pushing an all black stroller, and passing in between already stopped traffic going the opposite direction. She blended in entirely with the all black grill of the truck behind her.

From her perspective I was likely driving recklessly and should have stopped. If it had been possible for me to see that she was there I would have but the nature of that intersection makes seeing people crossing the street extremely difficult even in the best of conditions(thus my slow speed).

I actually ended up getting pulled over for this as I should have been and let off with just an unrecorded verbal warning. I don't make excuses for what almost happened and I never would have been able to live with myself if I had hit the stroller. While I do take responsibility for my side of the near miss and I didn't question the cop at all, there are situations where you can be looking for problems one way and miss the problem on the other side of the road. You can sometimes have the lighting play tricks on you making it seem like no one is walking there when really there is someone standing between 2 parked/stopped cars about to walk into the street.

I don't know all the details of this intersection or what happened with this lady and a 4 year old child but it is entirely possible that this was an unfortunate accident that is entirely within the doing of a responsible and attentive driver.