It is EXTREMELY unlikely for you to catch the virus from a child of this age, and it is VERY unlikely that either of you would be seriously ill or die if you did catch it from anyone. If you used the same odds all the time, you would not meet anyone or do anything between the end of September and March each year. Flu kills tens of thousands each year, and yes, children do pass on flu easily, and every year children and young people also die of flu. Covid-19, by contrast mostly kills the over 80s with existing health problems. The average age of a person dying of Covid is 82. The average age from all causes is 81, therefore Covid-19 is mostly taking out the people who were going to die of something very soon. What would the war-time generation think of us? Do what you think is right for you, on the balance of risks. Your husband is not being rational.