OP. I'm sorry if this is your child's name, but to be brutally honest, if my parents had called me Jowanet, I would think they had made a very poor decision to use that name, but I wouldn't feel they hated me, my parents always made me feel very loved & I don't see that what my name was would have changed that any.
I can't understand why someone would feel like that being given a name they hate means their parents hate them, unless they knew they were the product of an unwanted pregnancy or if their wanted a boy, not a girl (or vice versa).
I'd be worried about this child if they genuinely feel their parents hate them...but you know, sometimes kids are full of shite 😬
I had to look the name up as I thought it had been made up, but yes, as others have said, it's Cornish. However, even If was my Mum's Mum's name and she had died the day before I was born, I'd still not forgive them.
I don't think you have 'an attitude'. How you know the child is irrelevant.
Now, to your actual question...yes, I do think it's odd if parents call their children very different 'types' of names & I do think it 'can' create sibling disharmony and strange attitudes in/to their lives.
If siblings have very different types of names it does make me wonder why - but then I'm a very curious, interested person in general 😁