So if your bodies were both a boy and girl then Grandpa would be fine no matter which toy Marie or Jean played with? And because the boy-body and girl-body went to the toilet differently then all you had to do was have both parts at the same time! Struck by the clarity of your innocent logic, the things sitting between your legs were so astonished that they immediately changed. You-girl grew a cock. You-boy received a pussy. You-boy also became subtly more feminine, and would grow to become like you-girl and Mommy Michelle and Mommy Louise. And grandma, even if she was wrinkly.
“Grandpa, now.” Michelle sent her father a cross look, the harshness brokering no disagreements. Then, when she noticed former-you-boy shaking her head, the expression became more questioning.
"Fine. Can play dolls now!" You-J giggled happily and snatched the barbie from grandpa’s grip. He knew he had already lost and surrendered without a fight. Your mommies were mostly confused, but glad it hadn't turned into an argument on their child's birthday.
Michelle and Louise did figure it out later during bath time before bed. They weren't angry. Mostly asking questions about what happened. Saying you concentrated really, really hard didn’t exactly explain things. And trying to change back didn’t work either. Seemed you were stuck like this.
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16 years later.
Marie and Jeanne sat on either side of a cake with eighteen candles. You were surrounded by your mothers and maids inside one of your family's sprawling mansions. A strange sixteen years for M.J.
You had yet to find anyone else inhabiting two bodies. Becoming the undisputed champion of twin charades was the consolation prize for all that effort. Not that it meant you had stopped searching.
Sorting out your education had been a mess. Aside from the benefits of repetition, both Marie and Jeanne reading about multiplication tables was mostly a waste. So, instead, while you-M learned French then dissected frogs for biology, you-J practiced Chinese followed by singing lessons. And so on. Learning begets learning, go figure, so you still ended with straight As in everything. Then your ultra-rich mommies pulled a few strings to get you into university early where you had the pick for two degrees. ‘Wundertwins’ the media had called the 'twins' during your week in the spotlight following graduation.
Yet it was in fitness and fashion where your heart lay. The transformation that occurred all those years ago made your bodies identical. Making any differences between them so fascinating. In a kinda messed up way if you thought about it. Jeanne could run 0.14 seconds faster while Marie weighed 1 lbs less. All because of the way your bodies trained and ate differently. Clothes, accessories, hairstyles also couldn't be shared in the same way knowledge, sensations, and memories were. At times you could imagine Marie and Jeanne were different people like everyone else, you weren’t, but that didn't mean you couldn't pretend.
And you did that during most days, but when Michelle prodded you and helpfully pointed out the cake was melting the smiles you gave her were done with undisguised and perfect synchronicity. The lit candles fell under your two-pronged aerial assault soon after. Once you were old enough to fully grasp that others weren't like you, your mothers had made you promise not to tell anyone outside the household and close relatives. A handful of others also knew. Not until you were old and mature enough to deal with the consequences.
Which, as Michelle, Louise, and the maids sang happy birthday to your two blushing and embarrassed selves, you now were.