A friend of a friend of mine back then was one of the sound engineers on that recording – had no choice as he was on the staff at Decca and got lumbered with feeding them at lunchtime – came home muttering darkly about having to ‘herd two dozen jammy-faced northern brats through the streets of London to McDonalds’.

Er, I'm hypothesising that they love their Grandma becuase she often acts as sitter whilst their single mothers are at work... Charles are these all illigitimate children from your teenage years?

OK do I win a prize?

They are singing the Iris company song?

I know the why, but I don't know the who. One of "our number" was one of the school children backing Grandma (and, I presume, helping to put her teeth back in, oil the wheels of her bath chair, etc.).