He is an adult and gets to make his own decision regarding the vaccine. There is nothing you can do about it other than tell him (once) that you are concerned.
I agree with Esspee he is taking a chance every time he talks to anyone or goes anywhere and has been for 18 months so I doubt it will be any bigger a threat when his little one starts school, but if it is it is his choice, it’s worrying for you though he’s your loved son
I ve just read where the ‘Right said Fred’ singer has just been in hospital with CoviD after refusing to be vaccinated and after the NHS saved his life he is still saying he won’t be vaccinated That’s just pig headed and I think he should be charged by the NHS for his treatment
If the reason for your query is that your granddaughter might become a carrier of the virus (little superspreader) and you are concerned for your son then frankly my attitude is that he has made his decision and the consequences are his.
I would like someone’s opinion , my son refuses to get vaccination , I am childminder to my granddaughter and am very worried as she is starting school soon , any thoughts , I know all pros and cons so it’s not about that it’s just I would like other peoples opinion on how to deal with situation