Taking newborn out

Hey everyone! I really don't want to seem like an absolutely terrible mom but I'm trying to figure out what to do here. My son will be a week old on Friday and also on Friday my husbands amazing grandparents are celebrating their 69th wedding anniversary by going out to eat at 5 pm. If I kept my son in the car seat the entire time and had a thick blanket over him and only stayed until we finished eating do you think it would be ok or is it too dangerous? Please don't think of me as awful I'm just trying to figure out what to do. Thank you in advance!