While staring at the balloon, Judy nodded her head, as if she had decided on her next move.
"OK," she said. "First, a test. Let's see if it still works on you."
Judy stood up in front of little Jim and put the balloon to her lips. Jim smiled and wiped the tears from his eyes. He couldn't believe she was actually going to grow him older again.
"Thank you, Jude!" He squeaked. "I promise I'll make it up to you."
Judy blew a short, little breath into the balloon and Jim felt him body stretch just a little bit taller... Then, she let the balloon deflate, and Jim shrank back to toddler size.
"What?" he said.
Judy blew an even bigger breath into the balloon and watched as he grew a couple of years older, now looking more like a preschooler than a toddler... And, again, she let the balloon deflate, shrinking him once more.
"Hey," he piped. "What the hell?"
"Tsk, Tsk," she said. "Such a naughty word for a baby like you."
She took a deep breath and blew a huge FFOOOOFF into the balloon. Jim stretched out quickly gaining several years. The growth happened so fast, he felt almost dizzy when it stopped. Looking down at himself, he thought he was about the age of a kindergartner.
"Wait!" he said, but Judy just smiled and let the air out of the balloon. Seeing him shrink back to toddler size, she started laughing hysterically. Jim just glowered at her. He was getting real tired of being her little toy to play with.
"This is too funny!" she said. "Oh, I'm going to have a good time with this. Thank you so much for bringing it home."
"Please, Judy..." he started, but she held a hand up to him, as if to say, "Not interested in hearing it."
"Release," she said, breaking the spell from Jim.
Judy looked down at her body, running her hands over her 9-year-old frame. Then, without a word, she put the balloon down on his dresser and started to strip her soccer uniform off. After a minute, she was totally naked. Jim was too dumbfounded by what he was seeing to even think to avert his eyes.
Judy then picked up the balloon and said, "Control my age!"
Staring at herself in the mirror, she blew one short breath into the balloon. FOOOOFF. Her body stretched about half a foot taller, and a pair of small mounds started to swell on her chest. She smiled at her now older reflection and blew an even deeper breath. FFFOOOOOOOOFFF. This time her body grew both taller and curvier. Her legs stretched out long as her butt and hips swelled out. The mounds on her breasts inflated into real, round, hanging breasts. Her face looked subtly older as well.
"Oooh," she said in a more mature, deeper voice. "Looking good, Sexy!" she told her teen aged reflection. "I'm going to be hot in high school." Jim just stared, open-mouthed. He didn't disagree.
A deep breath, and she blew long and hard into the balloon. FFFFOOOOOOOOOOOOOOOFFFF. Her body seemed to swell in every which way. Feet, legs, butt, hips, breasts, hands... everything looked more adult. Her face was now that of a young, college-aged woman with no trace of her former girlish features. She looked her body up and down in the mirror and nodded.
"Release," she said and put the balloon down on the dresser.
The girl, who only a minute before was Jim's 9-year-old sister, was now cupping a pair of B-cup breasts and checking out her rounded ass in the mirror.
She frowned as she looked at her breasts.
"Hmmm," she said. "Not quite as big as I hoped." Both Judy and Jim were surprised to hear her voice. She started laughing, "I sound just like Mom, now. Oh my God!"
Judy picked up the balloon again. "Well," she said. "Let's see if I can have a chest like Mom as well. Control my boob size."
She blew into the balloon and her breasts inflated in pace with the red latex in her hand.
"Release," she said and put down the balloon. Now, her hands lifted a pair of weighty D-cups on her chest. "That's better."
Jim was speechless. Not only had his little sister grown into an 20-year-old knockout. She now had a pair of stripper-sized breasts. He knew he should look away. He knew this was his bratty little sis standing before him and not a real grown woman, but he couldn't help himself. She was a full-grown naked woman and probably the hottest one he'd ever seen up close even with clothes on.
Judy ran her hands up and down her curvy figure and moaned.
"So, nice!" she said. "Oh, God, I feel so damn sexy!"
Her hands kept running over her body, cupping around her huge breasts and massaging them. Jim just stared at her, helpless to do anything but stare. On a whim, she picked up her discarded soccer jersey and held it in front of her chest. She laughed. The 9-year-old-girl sized jersey looked so tiny compared to her voluptuous adult body. It was hard to believe she'd been wearing it just a few minutes ago. Then, she noticed Jim in the mirror behind her.
"Enjoying the show, little guy?" she asked and smirked.
Jim quickly covered his eyes and looked away. "Sorry! Sorry!" he said. "I didn't mean to..."
"'Didn't mean to' what?" He heard her ask. "Check out you sisters body, like a little pervert? Huh?"
Jim blushed. He really wished he'd never bought that damn balloon. There was a gentle sound of fabric hitting the floor. Then, he heard her walk towards the bed, her footsteps sounding much heavier on the creaking floorboards than before. Jim just cowered as she approached, his eyes shut tight.
"It's OK, baby," she said. "Mommy doesn't mind if you see her boobies." Cautiously, Jim peeked up at her from between his fingers. Her face loomed far above him like a giant, her massive tits hanging down above him.
Smiling at him, benevolently, she asked herself, "Well, what should Mommy do now?"