Church Bell

Upon hearing that her elderly grandfather had just passed away, Katie went straight to her grandparent's house to visit her 95 year old grandmother and comfort her. When she asked how her grandfather had died, her grandmother replied. "He had a heart attack while we were making love on Sunday morning."
Horrified, Katie told her grandmother that two people nearly 100 years old having sex would be asking for trouble.
"Oh, no, my dear," replied granny. "Many years ago, realizing our advanced age, we figured out the best time to do it was when the church bells would start to ring. It was just the right rhythm. Nice and slow and even. Nothing too strenuous, simply in on the Ding and out on the Dong." She paused to wipe away a tear, and continued, "and if the damn ice cream truck hadn't come along, he'd still be alive today.