I think it's important to remember that how at risk we all are have been developed by the government to make sweeping decisions about groups of the population. There will always be outliers, my nephew was fit and healthy, he died at 23 of something he should have brushed off in a week.
My former personal trainer was found dead at the side of the road having collapsed on his bike, he'd had a heart attach at 28.
My great auntie is 98, fell at home and broke her ankle, she has a whole host of risk factors and tested positive for covid, she was discharged home with a boot when she was ready and had no complications of covid.
There is a real risk of 'othering' people in order to make ourselves feel less worried. He has underlying conditions, she was obese, that family are BAME, and on and on.
My son is medium-high risk according to their criteria, he is Mixed race and asthmatic. 99% of the time he is perfectly healthy, but f the worst happened people would reassure themselves that it couldn't affect us as he was 'high risk'
Make the decision as a family that you will do what you can to avoid catching or spreading Covid, minimising risks where possible.