It's one of the most powerful songs about child abuse that I know……

I don't agree at all that it's a song about child abuse. In my Stan Kelly songbook "Liverpool Lullabies", the instruction at the top of the score is "Affectionately". The song is about a mother reflecting on the troubles in her life and imagining how things could be. It ends with the lines:
          But there's no one who can take your place
          Go fast asleep for your Mammy
It's clear to me that the child is loved.

The phrase "you'll get a belt from your dad" is hyperbole typical of Liverpool and means nothing more than "wait till your father gets home". It's the same as saying "I'll kill him" when someone has misbehaved big time. It doesn't mean that you're going to organise a drive-by shooting, at least not in the UK. It's just an expression and I don't think that you should read modern day attitudes to child abuse into a song that was written over 50 years ago.

Oh, and by the way, further to my comments above on Cilla Black changing the words: I have listened to a recording on YouTube where she sings "beggar" instead of "bugger" and that is the version most attributed to her on lyric sites …. but she did sing "blighter" at least once on TV . I know; I heard it with my own ears and it is not the type of outrageous change that is easily forgotten.

DC