A bit later Jim noticed that his whole family and his neighbor Leonard Gondman were getting ready for dinner, and figured he'd make the balloon's existence known to his whole family through a prank. He blew the balloon to near bursting and expecting that at worst this would be a prank he could undo said "Balloon Control my Mom, My Dad, My Sister, Mr. Leonard Gondman, and my own age." then walked down with the overinflated balloon.
The dinner table was full of food, and Jim was the last one down holding the balloon which irritated his dad who said "Jim would you put down that balloon? We've got a guest over."
Jim said "Oh fine" and then let go of the balloon which let the thing sputter as it flew across the dining room above the table. Jim had a grin on his face as he began to felt his clothes get looser and everyone shrinking in their seats. There was a moment of confusion and annoyance by most, but Jim's sister being only 8 figured out what was going on the quickest. The little girl's thin young body shrank to that of a toddler. It was frightening for the now baby who was screaming.
The adults who went from middle-aged to the prime of their life had seen that now Jim was a little child, but hearing the scream looked to the baby girl. Jim himself seeing the balloon was still more than half full broke in a cold sweat as he understood what was going to happen to his sister. His parents got to the panties and dress that now only contained a wet stain.
Jim's father making a quick judgement decided to do everything he could to try to catch that balloon before Jim became a fetus or cum stain and hopefully bring back his sister. His mother however seeing her husband go after a small target and being more emotional gave her small toddler of a son a hug hoping somehow this contact would keep him with them all. Instead with the father unable to catch the runaway deflating balloon the mother felt a weight on her abdomen and the closeness of the mother to the de-aging son caused him to transfer to her womb instead of regressing in his clothes like his sister.
Jim's mother was hysterical as her pregnancy reverted really fast, her husband saying "he was trying his best", and the Leonard Gondman was just confused unsure what to do as they became under the drinking age and their clothes became really loose on their bodies that were thinning and shrinking. A few seconds later Jim's father was 13 and not caring about the fact that his pants and boxers had fallen off as he was trying to get that balloon which he nearly had. Leonard Gondman was trying to help however he could, and Jim's mother was turned around as her younger form felt embarrassed by the half naked boys and the fact that her shirt was a dress she had to keep up or it would reveal her bare shoulders and mommy raised her better than that.
The father now 3 years old grabbed the balloon in the air which had just a bit more air to give out which was harder considering his wife was now a 1 year old... scratch that a pile of cum with the rapid rate of de-aging. Now all he needed to do was close the air from getting out and... His thought process took a little too long with his brain undeveloping at a rapid pace, and the balloon with only a bit of air left deflated completely leaving the balloon just above a shirt with a cum stain.
Leonard Gondman was still alive and existing, but just a few months old and confused barely managed to crawl out of his own shirt. His mind muddled as he didn't quite get object permanence yet. The idea that objects can in fact exist if you can't perceive them... and the balloon was out of sight.