As the girl started to change, Jack chosse to do some changes to his initial plan. First, 18 was not the limit anymore, they would age to 20, and mind changes would go along, since he tought it would be funnier.
The Virus worked faster than he tought, before his eyes, the former little girl was now an embarrased gorgeous brunette on her early twenties , triyin to cover her new assets ,while shreds of her not more fittin clothing could be seen on the grass.
Happy wit this results , Jack didnt wanted to wait for a natural spreading for the virus, and he wished for a virus vial on the hands of every kid on the park , and he was lucky , there was a lot of them , and his fun just started