It looks like the moo put the salt in her kid's tea by mistake. Ask for another glass and get over it. What kind of example is this setting for the kid? If you can't deal with dinner, how are you gonna deal with the rest of life?
I can't understand why she would want the waitress to appologize. SHE should be the one to say I am sorry, but I wasn't paying attention to what I was doing...
