As she heard the knock on the door downstairs Cheryl started to panic she couldnt just explain away her missing sister and her sudden gravid state she was going to have to bite the bullet and give birth to her sister. Grimacing , she picked up the remote and pointing it at her stomach she franticly punched in '+2 months' and pressed 'enter' and waited for the inevitable agony that was going to come. It took a few seconds for her to realize that she had entered the wrong thing instead she had entered '-2 months' as her belly shrank again Cheryl cursed, " Fuck me, this is going to suck..." she made sure that she entered the right thing this time and cried out in pain as her belly quickly swelled to a 9 month stage, grabbing a sock off her dresser she balled it up shoving it in her mouth to muffle her screams, as the contractions started an felt fluid gush out of her as her water broke and the contractions became stronger and closer together, 10 minutes of agony and pushing later Tiff was out of her and bawling heartily.
Cheryl sat on her floor panting and sweaty her swollen milk filled breasts leaking in response to the crying new born form of her sister. She grabbed a clean tshirt to wrap Tiff in and cut the cord with a pair of nail scissors after the placenta was expelled from her body, hopefully there was none left in her which would be bad to the extreme. she held Tiff up to her chest and grabbed the remote again, Cheryl looked at herself in the mirror and saw how huge her breasts had become her nipples were thicker and longer and her areola were bigger and darker more purple then pink and her nipples were steadily leaking droplets of pale yellow milk, colostrum, her mind supplied absently. Tiff was crying and she didnt want her mom to come upstairs so she placed her sisters mouth on the teat of her leaking right breast, Tiff latched on and started suckling right away. Cheryl winced as her womb contracted and at the strange feeling of somthing being sucked out of her body.
Cheryl decided to go slow in aging her sister back to 16 lest she press the wrong thing and have to go through her little ordeal all over again. Cheryl punched in '+3 months' and pointed it at Tiff and pressed enter, Tiff still sucking away grew to a three month old baby. Cheryl let her nurse for a bit longer until it started to hurt, she detached Tiff from her right breast which was now empty, sagging and floppy to her still turgid left breast, which Tiff took right to with renewed vigor and Cheryl winced again as Tiff became more aggressive in her feeding squeezing her breast with chubby hands as if to squeeze the milk out faster. Cheryl aged her sister up another 3 months and Tiff kept sucking away until Cheryls breast was empty . Cheryl detatched Tiffany who promptly burped and went to sleep, Cheryl dressed her sister in her oversized clothes and placed her on the bed. Entering '+6 months ' Tiff aged to a year old after that Cheryl aged her up year by year until her snoring 16 year old sister was passed out on her bed. Cheryl went into her attached bathroom with the remote and some clean clothes leaving her sister to sleep.
Closing and locking the door Cheryl looked at her body in the mirror she had stretch marks on her stomach and breasts, her areola were huge and dark , her nipples were thick and long- looking more like a cows teats then nipples- and her breasts were flabby and sagging. taking in all the changes pregnancy had wrought on her 18 year old body and the after pains she still felt from childbirth she vowed to herself to never put her body through that again. ever.
A quick few inputs and she was back to normal .. well mostly normal, she did give herself back the firm G-cups and the curvier build.