We each make our own parenting decisions and those concerning the risks we feel acceptable. Depends on so many factors. Age, health, diabetes control, family members exposed, risk behaviour of the guest, geographic prevalence of the virus etc etc etc. It is currently still against government advice for people to stay over in England (til tomorrow and then social distancing still needs to be maintained).
My teens haven’t liked all my decisions. When will they ever like all my decisions covid or not? I’ve felt mean making some of them when putting myself in their shoes. Some I’ve made for their benefit, some to meet legal requirements, some to protect myself. I’ve explained my reasoning, expressed I am sad it makes them sad and moved on. They’d be a whole lot more miserable if they felt responsible for me catching it having tried to force me to make decisions against my conscience.