On 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 2 people nearly 100 years old
having sex would surely 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, wiped away a tear and then continued, "and if that damned ice 
cream truck hadn't come along, he'd still be alive today!"