Mrs. Smith had always suspected her son, Mike, was having an intimate relationship with his roommate, Jennifer.
One night, Mike invites his mother over for dinner. All thru the night, Mrs. Smith watched Mike and Jennifer interact, and was pretty sure there was more than met the eye. Mike saw his mother watching them and assured her that they were just roommates.
A few nights later, Jennifer went to Mike with a problem.
"Ever since your mother was here for dinner, I have been unable to find the gravy ladle. Do you think she took it?"
Mike replied, "I doubt it, but I'll e-mail her and ask her anyway."
Mike sat down at the computer and composed the following e-mail:

Dearest Mother,
I'm not saying you did take the gravy ladle, and I'm not saying you did not take the gravy ladle. But the fact remains, since you were here for dinner, we have been unable to find the ladle.
Love always,
Mike

Two days later, Mike received the following reply from his mother:

Dearest Michael,
I'm not saying you do sleep with Jennifer, and I'm not saying you do not sleep with Jennifer. But the fact remains, had Jennifer been sleeping in her own bed, she would have found the ladle by now.
Love,
Mother

Moral of the story: Don't lie to your mother!