To not want my DS to have his name shortened?

[Saibuter]

I've namechanged as this will be outing. My son is 5 months, his name is Lucas. He was born a few weeks before we went back into lockdown so he didn't meet any family apart from my mum (I live with her) and my partners mum (he was living with her but now he's moved in with me to do more with DS).

Last weekend, he met my some of my partners family and they kept shortening his name and were calling him Luke and 'Lukey' we don't want his name shortened as a baby, obviously when he's a child he can decide for himself. A few of my family members have also called him Luke.

WIBU to tell them to call him his proper name or will it seem like I'm overreacting?

Ironically I really dislike being called by my full first name. It's reserved for my mother telling me off!

It will stop eventually by most people . My son is called joseph. We’ve never called him Joe. He doesn’t answer to Joe and yet his godmother writes it in all his cards and his teachers all call him Joe.