I used to have a cat that meowed at other cats in the same tone she meowed at humans. One time there was a cat stuck up a tree behind our garden, and our cat was walking around below the tree, meowing up at the cat up the tree, and she wasn't growling or anything. She seemed to be meowing like she would at us humans. And she didn't know we were there because we saw from out an open window. She was definitely meowing at the other cat.
Also she would meow at her brother. One time she was laying on the couch and her brother jumped up to join her and she meowed at him, as if to say "hello!"
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Female
Aged 32
On antidepressants
Diagnosed with ADHD, anxiety and mild ASD
I don't like autism being mentioned to me as I'm partly in denial.