So I had my baby about 2.5 months ago. His full name is Joseph Scott LN. Everyone calls him Joey. He has always been Joey, even since before he was born, and if the sex prediction had been wrong (if we had had a girl), I think I would have still wanted to call her Joey, just because that's what the baby was to me when I was pregnant.
I have never called him Joseph. After I told his aunt (my SIL) his name before we had him, and that we would call him Joey, she sort of flipped out saying that there was a weird kid she used to know that went by Joey, and that we "had" to call him Joseph.
She now calls Joey by his real name Joseph. I think it may be just to spite me or something because the first few times she has called him that, there was an odd tone in her voice (like a rebellious one), and thus so far. It's a bit annoying to me, just because we specifically told her what we were going to call him, and we call him Joey in front of her all the time.
It's not that big of a deal except that she's got a nasty tone in her voice when she calls him Joseph. If she wasn't so snarky about it, I'd have no problem.
Although, I think it may nip itself in the bud when she calls him Joseph one day in a few years, and he snaps back "my name is Joey!"
But would it bother you though?