True allergies to cow's milk are relatively uncommon. Only 2 to 3 percent of children are allergic to milk, according to the AAP, and almost all of them outgrow it by age 3. (Learn the difference between a milk allergy and lactose intolerance .).
The underscore [ _ ] (also called underline, underbar, low line, or low dash) is a character that originally appeared on the typewriter and was primarily used to underline words.
ninja is correct that an underscore is a legal character, but it should not be interpreted as a substitute for a hyphen. That is, if the correct email address has a hyphen, substituting an underscore should not work since both hyphens and underscores are legal characters.osts: 20,938. The underLINE you're seeing with the email address is either because it is a link on a webpage/email, or because it has been underlined in HTML-the underline is NOT part of the actual address that you have to fill in.