Mil says I need to watch what I feed my child

He’s not even weaning yet 4 months old and she has said to my partner when he’s here he won’t get any chocolate etc off her. Now my partner keeps mentioning things like he won’t be allowed sugar etc and that if I feed him what I want he will be fat and that won’t be good for him at school he seems to always do this once he’s spoke to his mum.

His mum plans to have our son one day a week when I finally go back to work and this is just putting me off.

Also don’t plan on feeding my son crap but I also am not going to overly restrict him if he has a treat on a weekend then I won’t feel guilty.

Am I being sensitive

She’s also said I’ve made a rod for my own back picking my son up when he’s upset