We were a bottom, tummy, wee wee, poo family. Without being twee, this is the way it was. 'Bum' would have been greeted with abject horror and a severe telling off!
However, language is always evolving, so the more widespread use of 'bum' nowdays is not shocking, just proof that semantic drift is in place.
My grandchildren use 'bottom burps' for - well, it's obvious, really - and I think that's great word usage.
I have just had a recall: I was at a friend's house and said 'crikey'. My friend's mother overheard and went bananas (another change in the use of a word?!) as she was very religious and I was blaspheming and in her house, too! I had absolutely no idea why she was so cross with me, as was allowed to use this word in my home but I learnt very quickly that a word can have different connotations.
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