Lost track and not sure what I’m repeating here any more but...

Another thought with what may start off as a cat’s meow is that I think their voices develop as they age and are perhaps influenced by us trying to imitate their sound back to them. Of the more extreme examples I can think of, Mewan became a definite (and repeated) “Eek Eek”. Starboard (and Oedipus to a lesser extent) “Wee-Oww”.

Although not that old when he died, Worthy was probably the most effective at letting you know (intensity of meow combined with facial expressions) how urgent he considered his request/demand was. You’d know eg. I need the toilet NOW.

Very short time with Furball but he was unusual in that he used quite a variety of Prrrt/Chirrup sounds. I had the feeling they were all supposed to convey different meanings but I never got beyond that with him.