This was not how the trip to Alpha Centauri was supposed to go. Alex and Sam were on the same colony ship headed towards what was to be Earth's first space colony. The invention of nearly lightspeed travel meant that the ship would be able to reach this neighboring solar system in just 5&1/2 years. Proxima Centauri b had temperatures similar to those of Earth, and for the past two decades, probes had been altering the atmosphere to make it breathable. Because of the long voyage, it had been decided that Alex and Sam would have their puberty delayed until some time shortly after their 18th birthdays. Alex was born in November and Sam in October, so their nanobots had been re-calibrated to give them their genders the December of that year, about a week after the colony ship landed. But the Colony ship hadn't landed, it had crashed after the landing gear had failed. Alex and Sam were the only survivors, as all the adults were on the bridge or in engineering when the ship crashed, while Alex and Sam had been in the reinforced cargo bay.
Sam logged into the ship's backup computer to check the complete damage. Most of the cargo had survived, more than enough for the two of them until the next colony ship arrived. The computer also sent him a strange alert about his and Alex's coming puberty:
"WARNING. LACK OF ADULT POPULATION FOR COMPARISON. ARTIFICIAL PUBERTY WILL PROCEED IN COMPETITION MODE"
Sam remembered stories of "Competition Mode" from his Grandfather. Competition Mode was the original form that artificial puberty had taken when the system was created half a century ago. It was a much simpler algorithm that paired adolescents based on who they spent the most time with, turning one of them male and one of them female based on who was the "dominant" person in the relationship. The new algorithm considered a bunch of other factors, including the gender-ratio of existing adults, personality, and stated desire for one gender or the other.
Sam grew worried. Alex had always been a bully when they were kids, and Sam didn't relish the idea of being a woman when he was the only man on the planet for 10 years. He didn't think Alex was capable of anything too horrible, but he would probably assert himself as the boss and force Sam to do most of the work. "but", Sam thought, "he can only do that if he knows the programming changed." Sam decided to hide the notification about the change, and see if he could subtly push Alex towards becoming female. If he was the stronger one, Alex wouldn't be able to boss him around.
One month passes, and...