Bob and Nancy were celebrating their 50th wedding anniversary. After 50 years, Bob wanted to know if Nancy was always faithful. Bob asked, "Have you ever cheated on me?"
Nancy replied, "Yes, three times."
"What?!", yelled Bob, "When?"
Nancy said, "Remember when the septic tank flooded back in '69 and we couldn't afford to fix it? I convinced the plumber to fix it for free."
"And?" Nancy said, "Remember when you needed heart surgery in '75 and we didn't have insurance? I had the doctor treat you for free."
"And the third time?"
"Do you remember when you ran for mayor back in '89 and you were behind by 200 votes..."