My daughter's friend is lactose intolerant. What foods should we avoid when we take out to eat with us?

You'll want to look out for anything that contains milk, butter, cream, buttermilk, cheese, or ice cream. This means pizza is off the table (it almost always has cheese), and much Italian cuisine like lasagna or alfredo sauces must be avoided. You also need to be careful about fried foods, because batters often contain milk or buttermilk. Ask about the ingredients of bread, as these can contain butter: croissants typically do. Even salads can be a concern, because many restaurants will add cheese as a topping, even without listing cheese on the menu. Desserts are also problematic, because chocolate nearly always contains milk, as do most ice creams. Look for vegan products where you can, such as vegan cheeses and vegan ice cream, which can be delicious.