Judy had an idea
She was already tall for her age at 4’8, but she wondered how it would be like if she was taller than her brother, while he was at his normal size.
“Jim, I’m going to grow myself taller.” She said to Jim
“Why? You’re already tall for your age” he replied
“Exactly, and I want to feel how it is to be even taller. To be taller than you, just not when you are well… shrunk”
Jim didn’t want to outright say no to his little sister after she helped him like that, but he also didn’t want her to close the alarmingly small height gap they had despite their three year difference.
“But you’re going to stretch out your socks if you do that!” He excused.
“So I’ll just remove the socks” she replied while doing so.
“But… fine…” Jim said, not thinking of another excuse.
“So…” Judy said holding the balloon. “Control my height”
“Is this how I was meant to do it?” She asked Jim
“Yes, you now have to blow it up” he answered
“Ok, so…” she said as she moved the balloon to her her mouth and blew it up.
She felt strange, as if her legs were stretching, and quickly stopped, while holding the balloon so the air won’t go out.
“Well, this felt weird” she said while moving her sight to Jim. Getting closer to him, she saw that they were at eye level with each other.
“I’m as tall as you now!” Judy said in a cheerful voice. “And it’s not that you became shorter. I became taller!”
It felt weird to Jim. Not as strange as looking at his sister multiple times his size when he was shrunken, but still weird.
And then Judy took a few more breaths, each time looking at Jim inbetween.
After the second breath, she looked down on him a bit.
Third one, a bit more.
In the fourth one, it became very noticeable.
“Looks like I’m your big sister now” Judy said jokingly
Fifth, sixth, and seventh and she really stood out over him.
She stopped at the eighth breath, and looked down at Jim. She absolutely dwarfed her older brother, by at least a foot. He was only at level with her flat chest.
“Well, how does it feel to look up at your sister, ‘little’ brother” she joked as she bent down to meet her brother’s face.
It was extremely strange to Jim. Sure, the difference wasn’t as extreme as when he was smaller, but her body was now elongated, due to making the balloon control her height, and not her overall size.
“I mean, I already looked up at you when I was shrunken, but now you look all weird and skinny.” He said
Judy then took a look at herself. Her body was the same, except for the fact everything about it got longer, without changing its thickness. That meant that she was extremely tall, but just as thin as before. A very tall and lanky 9 year old, with clothes that were far too short for her body.
“I am very tall and skinny now…” she said in awe. “I wonder just how tall”
“Jim, can you go and measure my height?” She asked Her brother.
Jim realized he wouldn’t be able to convince her otherwise, so he agreed.
Judy stood against the wall, Jim grabbed a tape measure and then stood up on a chair to reach the top of his sister’s head.
The results shocked him.
“Looks like you are 6 feet tall” he said in a surprised tone. His sister now had a foot and two inches over him.
“Wow! I love it!” She replied
“But remember, you can’t stay that way. Mom and dad can’t see you like that. And I got a message that they’re coming in 10 minutes.”
Jim was right. They would have been terrified about the changes to their daughter, and then the secret about the balloon will be revealed to them.
“I guess you’re right” she replied.