Originally Posted by
missdimeaner
Most kids are savvy enough to manage this, even better than adults !
I travelled solo a lot when I was about 8 (on British Rail) involving two or more train/platform changes - it was a great adventure for me.
If you are really concerned that your ? year old will have a problem then an accompanying adult is the only sensible way forward.
Give a twelve-years-old kid an internet-connected phone and some YouTube instructional video access and it seems they can do way more than adults could do on their own twenty years ago. For better or for worse.
Heathrow has free wifi of some sort at much of the airport. And between live video chat and asking people what to do, a capable 12-year-old should be able to manage the airside transit. My bigger concern would be what happens if the passenger gets stranded overnight at LHR.