At lunch, you are looking for your advisor, when Dave Savitt hails you. "The rest of the staff are busy looking for the missing chalk, so I'm conducting all of the advisor meetings today. In fact there's not much to discuss this week, except that I'm supposed to tell you to call your mother."
"But I call my mother every day," you reply, "don't you?"
"Oh... er..." Dave blushes. "Actually, it's been a while."
"So who do you talk to when, you know, you need to talk?"
"You're right, you're right: when I need help, it does seem like my mother always has the answers. And she always seems to look forward to receiving phone calls, as long as I call between the hours of 10 am and 10 pm (her time). Otherwise, she won't even pick up the phone. But I just don't have the time these days to give her a ring...."