Bodyofeyore
If you are feeling mentally stronf, read the Washington Post article.
Once i read that article, i realised it isn't about forgetfulness per se.
One man left his child in the car parked in his work carpark which his office overlooked. During the day, the alarm kept going off because the poor, poor child was wriggling / struggling / trying to get out. The father kept walking over to the window and flicking off the alarm with his keyfob, assuming the alarm was malfunctioning. He had not "forgotten" his child in thr normal sense.
Imagine the guilt that father lives with.
I actually think it must happen more often than we think in the uk, too, but because of the climate in the uk, the poot babies do not die of heat exhaustion but are rescued at the end of the day. We don't hear about it because it does not result in death. We do hear of these tragedies here in France (where i live). This event linked above was in Italy and the Post is talking about US tragedies.
I would be amazed if it's not common in the Uk but just without the utterly tragic ending, instead a very hysterical and dehydrated baby and relieved and embarrassed parents.