Summer's the prime time for visiting friends and for them to visit you. But, as my grandmother used to say when my family would visit her, she was happy to see us come and she was happy to see us go. It wasn't that she was inhospitable; she loved having us over. It was that she understood the rule of visiting. There's a rule about how long guests should stay that she often quoted...Fish and guests, she liked to stay, smell after three days. We remember this rule when it comes to cooking; we also remember it when it comes to guests. Three days is a perfect long weekend to catch up with friends. Day one, we're happy to see them; day two, a full day of adventure; day three, we're ready to settle back into our routine. Recently, we've found that the number of guests follows a similar pattern: one guest doesn't disrupt our routine that much. We get the one on one time with our friend we were hoping for. Two guests can also be fun: they have each other to entertain themselves if we have plans, errands or work that we have to take care of. Three guests means four for dinner, a nice even number. More than that though and suddenly, the house feels crowded.