Kimberly and the Carlsbad Caverns

When my parents were young, my Dad enlisted in the Air Force to avoid being drafted into Vietnam.  One of the places he was stationed was Holloman Air Force base, where Kimberly, my older sister, was born.  Being new parents while stationed half-way across the country from their own families was tough.  So to stave off the feelings of loneliness and isolation, they made a habit of taking frequent trips to various landmarks around the area.  They figured they may as well make the best of what they had.
The trouble is, it was New Mexico.  There's just not a whole lot to see out there besides windswept deserts and the occasional top secret spy plane flying over Roswell.  But there are a lot of National Parks with forests, mountains, and even some intricate cave systems.  Luckily, Carlsbad Caverns, one of the largest and most prolific cave systems in North America, was only a 3 hour drive away from the base.  So once their newborn baby daughter was old enough to make the trip, they packed up the car and headed out on a fine spring day.
Upon arrival they signed up for a ranger guided tour through the caves.  Now, since you can't roll a stroller through the rocky terrain of a cave, Dad had brought along a baby backpack to carry my sister down.  So before they set off into the caverns, Dad loaded up Kimberly onto his back while Mom wrapped her up in a little baby jacket and bonnet to keep her warm in the chilly cave system.  Fully prepared for the hike down to the cavern's Underground Lunchroom and visitor center, the tour group set off following the park ranger single file down the trail.  Dad descended into the caves first with Kimberly strapped safely to his back while Mom followed right behind him to keep an eye on her baby daughter.
The tour group was about halfway through their 750 foot descent into the cavern when Mom looked up from her exertions to see Kimberly happily cooing and giggling as she played with her bonnet.  It was a simple summer cap with a frilly laced brim and a single elastic cord that wrapped around Kimberly's chin to hold it in place.  She had managed somehow to slip her chubby little hand underneath that elastic band and was merrily tugging on it, giggling with delight to feel it tugging back against her.  Kimberly was evidently feeling quite macho that day because she then decided to stretch that poor elastic band as far as it could possibly go when suddenly...
SNAP!  ...mmmbbbwwwaaaAAAHHH!!!!
The band had slipped through her tiny fingers right when it was stretched to the brink and come flying back at the infant, popping her square in the mouth.  Never before has such a happy cooing baby switched so quickly to such ear-piercing irate screams.
As her squalling echoed off the cavern walls, the tour group began to notice that the high-pitched wails were not dying out as you might expect, but instead were growing louder, more urgent, and higher pitched.  Such screeching could not possibly be emanating from the voice of this young child.
Carlsbad caverns is home to over 17 different species of bats.  A recent survey counted over 700,000 individual bats resident in the caverns at once.  In her cries of fear and pain, Kimberly had somehow hit an octave that the bats recognized as a child in distress and all 700,000 of them came flying down from their roosts to rescue the young one.
As the bats began swooping down to attack the tour group, the ranger gave orders for everyone to immediately duck and cover to protect their eyes and faces from the claws of the assailing bats.  Dad, being the well trained military man that he was, quickly followed orders and hunched over to avoid the assault.  Unfortunately, he did so with Kimberly still strapped firmly to his back.  So as he bent down to escape the onslaught, Kimberly was hoisted up to face a rushing tide of screeching, fur-covered, claw-tipped leathery wings.  This did not improve her mood in the slightest and her now panicked cries only served to incite the bats further.
Seeing her child in distress and now exceptionally vulnerable to the attacking bats, Mom leapt into action.  She jumped from her own prone position onto Dad's back while wildly batting at the bats with both arms.  Dad, already unbalance by his own crouched position, was further upended by the flailing weight of Mom upon his thoroughly unprepared back.  In short order the trio went tumbling down the trail until their decline was finally halted by a pair of looming stalagmites.
Luckily, in the tumult Kimberly's cries were finally muffled by the weight of her parents' bodies; reassuring the bats that the alarm had been resolved so they could finally retreat back to their roosts.  Needless to say, after checking that everyone in the tour group had survived relatively unscathed, the park ranger immediately escorted my sheepish parents out of the caverns.
That is why, to this day, children under the age of 3 are not allowed into Carlsbad Caverns.