Polly never gave her transformation a lot of introspection. Back then, all she cared about was that her brother gave her something that made her feel a whole lot better. But over the next few days, Polly just kept growing bigger and sprouting white fur. She wasn't particularly alarmed that she was turning into a polar bear. Now she was taller and so soft and fluffy. She didn't even think that Jeremy had done anything wrong until he was arrested. Polly was glad he didn't spend long in jail, but she ended up becoming part of another family.
Polly did love living with the Whites. Her memories of her and Jeremy's birth parents have grown very hazy and Jeremy had done as much as he could to fill in that role. But Polly quickly acclimated to living with the Whites. It didn't take long for Mr. and Mrs. White to formally adopt her and Polly soon took to calling them 'Dad' and 'Mom'. Polly also liked having Marcy as the big sister she never had. And while it was easy to see Chilly as a brother, Marcy explained that Chilly was her boyfriend and won't officially become family until they marry.
Over the years, Polly grew. Not so much physically as she did mentally. She came to understand why Jeremy was arrested, but she didn't fault him or Heather for it. She was glad they ended up together and having kids. Polly liked being an aunt, even if she was relatively young to be one. She knew how a second dose of the Animalian virus would make her an adult, but she wasn’t interested in growing up just yet. Well, she was curious about what she’d look like when she grew up like any young teen, but she didn’t rush through to adulthood.
Of course, that all changed when she was told about her pituitary problem. She knew her development would be a little different, but she didn’t think it would be that much different. She still didn’t blame her brother for it. Jeremy was only trying to help her, he couldn’t have been able to predict how his formula would change her, let alone the long-term consequences. Polly knew that she didn’t have her second dose now as she hadn’t developed any troubles with her bones yet. But she knew from Marcy that high school could be a really awkward time and she should take her second dose now so she’ll have the summer to adjust to her new body.
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Once Polly made her decision to get her second dose, it mostly became a question of how to administer it. The most clinical method was a simple shot as a sample from any other Animalian that was older than her would be enough to trigger it. However, Mrs. White was firm that such a transition required a more nurturing hand to guide her. As such, she'd be the one to help Polly change once her vaccine was deactivated.
When she and Polly were alone in the changing room, Mrs. White proceeded to give her adopted daughter 'The Talk'. Polly already had a basic grasp on where babies came from, but now she was being told the particular parts of baby-making. It was...a rather awkward conversation to have. At least Mrs. White had done this before with Marcy when she was getting ready to go to high school herself. Of course, she hadn't anticipated Marcy putting that information to use so soon.
"The important thing is that you're going to become a grown woman and be considered a legal adult," said Mrs. White, "And being an Animalian will mean you will have a drive for it."
"Like what you and Dad do in your bedroom? And Marcy and Chilly in theirs?" asked Polly.
"How much of that have you seen?" asked Mrs. White, concerned.
"I haven't seen it, but I can hear some things and sometimes I smell something," said Polly.
Mari sighed. She, Greg, and Marcy have tried to show less activity around Polly, but they all had needs and urges. "Look, the point I'm trying to make is that once you're double-dosed, you will have the freedom to...exercise your sexual side, but please be responsible," she said, "I'm not expecting to immediately hook up with another bear and I won't stop you from doing so, but please take some precautions."
"Don't worry, Mom," said Polly, "I'm not ready to be a mom yet."
Mrs. White hugged her. "That's what Marcy said too. Of course, things are different. She's finishing up college. Or I think she is. I'm not sure how much more work she has to do to become an astronaut. But I know a lot of her old classmates are getting married soon and she'll probably want to marry Chilly before long."
"Then I can be her bridesmaid," said Polly.
"Yes, unless she's wanting to do one of those mass weddings," said Mrs. White. The Animalia Ambassadoria cast weren't the only ones getting married at once. There were plenty others from the WSA Class of 2020 who have waited four more years to finish college and finally marry their mates. Mrs. White thought Marcy was still focused on her studies, but that didn't mean she couldn't take the time to marry Chilly.
"Well, are you going to help me grow now?" asked Polly.
"Oh, right," said Mrs. White, "Just give me a minute." She turned around and lifted up her shift. Polly could hear the trickling sound of a glass being filled and the small hum of pleasure her adoptive mother gave. Lowering her shirt, she turned back around with a cup full of milk. "I assume you'll be wanting a bit of privacy as you change," said Mrs. White, handing her the cup.
"As long as you're not too far away," said Polly, taking the cup.
"We'll be with you as soon as you call," said Mrs. White, kissing Polly on the forehead. She then headed to the door. "And I hope you'll still see me as your mother."
"Of course I will, Mom," said Polly. Mrs. White smiled before walking out the door and closing it behind her.
Polly waited until she was sure her mom had gone a far enough distance before she drank the milk. It was probably fattier than cow milk, due to how much weight bears need to put on before winter, particularly polar bears. She got out of her clothes before the tingling started. She wasn't sure how much bigger she was going to get, though everyone expected her to be huge even for a polar bear.
Already an Animalian, Polly didn't become more of a bear than she already was. Instead, the virus in her system focused on completing her maturation and fixing any physical problems it could find. Polly groaned a bit as she grew taller, though she wasn't rising up as fast as expected. There were small little crunches as her skeleton modified her proportions, becoming less childlike as she grew. If she weren't growing taller, it could be suspected that the Animalian virus was mostly just redistributing her mass. Bit by bit, Polly was looking less like an oversized child and more like a teenager.
Then Polly felt a surge of power go through her. Her muscles became filled with as much energy as they could stand before they started expanding to fill more. The pudge clinging to her middle was quickly burned up for fuel, leaving her nicely toned. Her muscles became more obvious through her thick white fur as they grew. Polly knew her mom and Marcy were in good muscular shape, but it was clear that Polly was meant to go past them. Her shoulders expanded more to make room as she started to look like a sculpted marble statue. "Wow, this feels amazing," she said, her voice having gotten a lot deeper.
Then her womanhood started catching up with her new frame. Her small breasts had nearly disappeared as she grew in height and muscles. Now they were becoming rounder, more distinct from her pectorals. Polly felt one and bit back a moan. She was surprised how sensitive it would feel growing into her hand. When her fingers eventually touched her black nipple, Polly couldn't hold back the moan. She tweaked the nipple as her hand filled more. Her breasts growing from a handful to large white orbs.
But her womanhood was also awakening in her lower body. Her rear started regaining some of the fat it lost as it filled out to a pleasing shape. Her hips were also getting a nice amount of padding as her body became ready to bear children of her own. Speaking of which, her pussy was becoming engorged as estrogen coursed through her, completing the womb that had been starting to develop inside her. Polly's other hand traced her lower lips, feeling the needy wetness. She hesitated a bit with her claws, but soon she inserted one, then two, then three fingers inside her. Polly's voice had definitely matured to the woman she had become as she tweaked her nipple with one hand and fingered herself with the other. The pleasure built up higher and higher until Polly let out an ursine roar, her nipple letting out a small fountain of milk as her other hand became soaked in her own juices.
Polly took deep breaths as her body cooled down. Part of that was from a polar bear's natural temperature regulation. When she focused on the room around her, she could see that things have gotten tinier to her. Marci and her mom were a little under 8 feet, but Polly was pretty sure she was taller than either of them, maybe taller than her dad or Chilly. Marcy took a few cautious steps to look at herself in the mirror. "Whoa," she said. She paused before saying again in a deeper voice, "Whoooaaa..." She spoke with her normal voice, "I sound like an adult now." Her voice did have a rich timbre that reflected her new maturity and size very well. And she had both in spades.
While Marcy and her mother had bodies of amazonian bodybuilders like most large Animalian women, Polly was definitely of a class higher than them. She looked like a snowy mountain carved into titanic muscles. She flexed one thick arm and said, "I bet I'm stronger than Chilly or Dad. Heck, I might be stronger than Jeremy." Of course, all of her mass wasn't just muscle. She was also given a very generous pair of breasts. She might be in the same size range of the cow Animalians, the ones who were beef cattle, not dairy cows. And she had a luscious set of hips and a round bubble butt. No, she needed to start thinking of herself in adult terms. She had a sexy heart-shaped ass. Polly turned around to look at her ass in the mirror. She had to brush away her hair to get a full view. Unlike Marcy, Polly was a darker shade of blonde. Ironically enough, it was honey-blonde. Bear Animalians love honey as much as their feral counterparts, but some like it more than others. Polly hadn't paid attention to her hair during her change, but now it flowed down her back to her ass like a honey waterfall.
"I think this more than makes up for Jeremy's mistakes," said Polly. She knew Marcy had a side-gig as a mascot for Coca-Cola, but she wasn't as dependent on it now. Polly was pretty sure she could pick up that job rather easily. Heck, any kind of modeling would accept her now. But she couldn't exactly parade her body around with nothing at all. She went to the door and called out, "I'm done changing. And I think I'm gonna need something extra-large to wear." She took another glance down at herself and added, "Make that extra-extra-extra-large."
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Polly soon got her answer of how big she was when she was able to look her Dinotopian brother in the eye. To say Jeremy was flabbergasted would be an understatement. He gaped at the huge polar bear woman she had become and said, “Oh, Polly, I’m so sorry.”
“Sorry for what?” asked Polly, “That my life is better than it ever would be before? Maybe if I had a straightforward conversion instead of you trying a derived formula, things might have turned out differently. But I’m happy with how everything turned out.”
“But I took away your chance for a normal, happy childhood,” said Jeremy.
“Jeremy, I did have a happy childhood,” said Polly, “And ‘normal’ is such a subjective word. Sure, I spent it with a family of polar bears. But that’s hardly different from a lot of other Animalian families. And I got to spend those years with you too. I don’t think I missed out.”
“Except on your teen years,” said Jeremy.
“Did I? I’m still going to high school. So I’ll have the body of a grown woman. I’ll hardly be the first and I doubt I’ll be the last,” said Polly, “I’m as normal and happy as I can be.”
“Asides from being a giantess,” said Heather, “Not that I’m disparaging or anything. You look fantastic.”
“I do, don’t I?” asked Polly, flexing, “I don’t think Jeremy’s going to call me his little sister anymore.”
“Incorrect,” said Jeremy, “Just because you’ve gotten closer to my size doesn’t mean you’re any less the younger sister.”
“Is that so?” asked Polly before grabbing her brother in a big bear hug. It seemed to be more than just a show of affection the way Jeremy’s bones were audibly creaking.
“Ok, enough, enough,” squeaked Jeremy. Polly released him, allowing him to get his breath back. “You really are strong now,” he commented.
“I know, right?” said Polly, “I could easily win a bodybuilding competition like this.”
“If I had a dollar for every newly converted Animalian who said that, I’d be able to buy a big ranch house,” said Jeremy dryly.
“Don’t squash her enthusiasm,” said Heather, “Besides, she really does have the potential.”
“Well, I would hope that my younger sister would have higher aspirations than just flexing and posing,” said Jeremy.
“How about being in Animalia Ambassadoria?” asked Polly, “After all, some of their members are graduating.”
“I’d like to see that,” said Heather, “Though you will take up most of the screen.”
“As long as you’re more focused on reporting than being the center of attention like others,” said Jeremy.
“Animalia Ambassadoria does a good job,” said Polly.
“I mean the Quasi-Raccoon Cuties,” said Jeremy.
“They’re not as bad anymore,” said Polly, “They’ve gotten their act together.”
“And you’ll need to work on yours if you want to be working for Animalia Ambassadoria,” said Jeremy.
Polly nodded. But she had all summer to work on that as well as get used to her new body and the urges that came with it. This was certainly going to be a summer to remember for her.