Based on some very constructive comments by @Remobrat - Thanks!!
Anna and Sharon had been talking, amongst other things, on the sofa in front of Sue’s playpen, with Sue watching on helplessly.
“Now we’ve got the money available”, said Sharon, “let’s up the game a bit. Time to really play with her…”
Sue’s eyes widened with terror, and she moaned loudly into her gag…
Boxes started arriving a few days later. Sue was also finding it more difficult to move; she kept losing her balance, then finding out she wasn’t strong enough to pull herself back upright. She’d long since been unable to pull herself up the side of her playpen.
“Looks like the modified food is working”, said Anna, with a giggle.
Opening one of the boxes, Sharon pulled out a pink collar, with a heart swinging from it.
“I had this specially made”, she said. “It cost a fortune, but it’s worth it. It disrupts the wearers voice, without permanently damaging it; it means Sue can talk, but unless this collar is switched off, it will all come out in baby talk. Come on, give me a hand fitting it. I can’t wait to hear it working.”
Anna easily picked up Sue from her playpen, and Sharon fastened the collar round her neck. At the same time, Anna’s nose wrinkled.
“I think someone needs changing…”, she said, with a grimace.
She picked Sue up and laid her on her back on a blanket spread over the table. She then proceeded to remove Sue’s nappy and clean her, while Sharon was watching. Sue went red with embarrassment, squirming. Anna smacked her on a clean bit of backside, then went back to cleaning and powdering her. She then fitted her with a new nappy and sealed it on.
Once Sue was vaguely tidy again, Anna went to dress her.
“Hang on”, said Sharon. “Her new romper suit has turned up. Let’s fasten her into that. I had it tailor made for her, with locking fasteners. It’s really thick latex. It’s all in pink, with little ponies printed on it, and comes with a nice frilly bonnet. Isn’t it cute?”
Sue tried to get away, but her legs wouldn’t let her. She was soon fastened into her romper, and there was a click as the zips locked.
“I really like the inbuilt mittens”, Sharon said. “She can’t use her hands at all.”
“I think it’s time for her nap, anyway”, said Anna. “Is her new room ready?”
“Yes, the decorators finished yesterday evening.”, Sharon said. “You’re going to love this, Sue. Compared to how you kept me, you’ve got a life of luxury.”
Sue wailed as she saw the new room. Pink was everywhere, and everything was plush or fluffy in some way. A mobile hung from the ceiling, over a brand-new cot. There was a baby alarm sitting on a shelf, next to a cupboard full of soft toys. Everything was brand new.
“I hope you appreciate all this,” said Sharon. “We’ve done all this for you.”
Sharon pressed a button on a box by the bed. Lullaby music started playing.
Anna put Sue gently into the cot. Sue mewled quietly, trying to hold onto Anna, but she easily dislodged her.
“I’d get some sleep if I were you. You’re going to need it.”
Anna walked out, turning the lights down with a dimmer then shutting the door.
Sue cried herself to sleep…
Next morning Anna, still in her nightie, came in to check on Sue. She reached in and unfastened the cords on her dummy, removing it.
As soon as the dummy was removed Sue started pleading with Anna.
“Please! Don’t keep me like this! I’ve got a job to go to, a life waiting for me! I… waah, goo goo!”
Sues eyes opened wide as she suddenly realised she could no longer talk properly. Anna had pressed her thumbprint on the activator on the collar…
“It works beautifully, Sharon!”, she called. “Baby’s gone goo goo!”
“By the way, you haven’t got a job or a life waiting anymore. They’ve all heard about your nervous breakdown. Seems the stress of caring for your stepsister, who was just a bit off colour in the end, was too much…!”
Sue tried to beat her fists on the side of the cot, but her co-ordination was so bad now she missed completely and ended up flat on her front in the cot.
“Oh, by the way, Sharon and I have a dinner date at Falcon’s in town later. That was one of your favourites, wasn’t it? Your mother has offered to babysit for the evening.”
“She’s aware all about your ‘disability’; she says she feels very sorry for you and will do what she can to help. I’ll change you just before we go out, so she shouldn’t need to, but I’ll tell her where the nappies and powder are just in case.”
Sue had no intention of letting her mother see her the way she was!
Sweating with the effort, she struggled to stand up, then started violently shaking the cot. She also took a swing at Anna.
“Still some fight in you left, I see”, said Anna. “Oh well, at least your backside is clean at the moment…”
She reached in and pulled Sue out of the cot. Then, to Sue’s absolute amazement, Anna bent her over her knee.
Whack!
Whack!
Whack!
Whack!
Anna paddled Sue’s rear, really putting some effort into it. Sue howled. Sharon came in at the noise…
Whack!
Whack!
Whack!
Whack!
“The little twit’s trying to stop us going out by misbehaving”, Anna said. “I think I’ve convinced her that’s a bad idea. I have, haven’t I?”
Sue nodded, weakly.
Anna just unceremoniously dumped her back into the cot.
“Behave!”, she said.
Sue cried herself to sleep…
A few hours later, Sue was still asleep when her mother, Alison, turned up to babysit.
She’d heard all about Sue’s breakdown from Sharon; still, it was a real shock to see her daughter asleep in her romper suit in a baby’s cot. Unable to stop herself, she picked Sue up and cuddled her.
Sue, half asleep, snuggled up against her mother. She was starting to behave like the baby she was being forced to be, so her mother was really surprised when Sue tried to find her breasts to suckle…
Recovering from the shock quickly, still holding on to her daughter, she went and warmed up a bottle of feed in the kitchen and gave it to her.
Sue quickly sucked it all down, contentedly, curled up in her mother’s arms.
Alison was still cuddling Sue as Anna and Sharon came back from dinner. Their mouths opened wide in amazement…
“You can ask me to babysit anytime”, Alison said. “She’s beautiful like this…”