The thing about incomplete-written programs is that they can find unintended ways of following their orders. That could cause a lot of trouble with regular computers, but ones running a Chronivac could be more dangerous. For instance, Simon had set his Chronivac to gradually take his father's place, which it successfully had. It had even made Simon de-conceive and re-conceive John to become his biological father. However, Simon wanted to punish his neglectful mother as well. After the Chronivac finished swapping roles for Simon and John, it was to make him Kim's father as well.
However, he hadn't specified who Kim's mother and his new wife was to be. That left the Chronivac stymied and unable to proceed. For a while, the only other female around was Simon's former sister, 5-year old Nichole. The Chronivac preferred not to make siblings into spouses unless it had been told to. However, it kept Nichole as a possibility until a more viable target appeared. Then Amy appeared at the house. At 19, she had very briefly been Simon's boyfriend but became a more intimate lover of John when they were in the same age range. The Chronivac determined she would be a much more suitable wife and mother in the new family arrangement.
Of course, since it was an open-ended program, the Chronivac was free to interpret the outcome as it deemed best. And like most machines, it preferred efficiency. Its thought processes went something like this:
Subjects: Simon (30), Kim (30), Amy (19), John (12), Nichole (7), Stored years (26)
Nichole: Underutilized reciprocal of excess years
Kim: Current wife to be made into daughter
Simon and Amy: Intended parents, age of 30 permissible to have 12-yeard old son
John: May require rebirthing to match new mother's DNA
Current age goal parameters: Simon (34), Kim (12), Amy (34), John (12), Nichole (32), Excess years (0)
Current relationship goal parameters: Simon (Husband-Amy, Father-John, Brother-Nichole, Uncle-Kim), Amy (Wife-Simon, Mother-John, Sister-in-law-Nichole, Aunt-Kim), John (Son-Simon, Amy-Son, Nephew-Nichole, Cousin-Kim), Nichole (Sister-Simon, Sister-in-law-Amy, Aunt-John, Mother-Kim), Kim (Niece-Simon, Niece-Amy, Cousin-John, Daughter-Nichole)
Dispensing excess years.
The first thing the Chronivac focused on was using up some of the years it was currently holding in storage. It began with a simple dispersal of half of the stored years. 4 years for Simon to make him reach his goal age of 34. 6 years for Amy to start with. 3 years for Nichole to start with.
Amy's changes were a bit less dramatic since she was already near the end of puberty. She did get about an inch or two taller, but her body remained mostly the same. What mainly changed for her was her memories. Earlier that morning, she was getting ready for college. Now those college years were flying past her. She remembered studying to get her degree in medicine. She was still undecided in what field of medicine she wanted to specialized in, but being an intern didn't pay enough to keep her afloat while paying off her college debt, so she was still doing some babysitting jobs around the neighborhood. She had known Simon and Kim for years and she used to have a bit of a crush on John when she was a kid. Of course, John is 9 years older than her and married with kids. All Amy was doing here was looking after their kids for the day.
Nichole's change was considerably more noticeable as she got closer to teenhood. She put on 1.5 feet in height as her baby fat started draining away. Her pink dress pulled up her body before it became a t-shirt of the same color. A pair of jean shorts appeared on her as her shoes became sneakers appropriate for her new age. Her face thinned out slightly as new teeth popped into her mouth. Her dark brown hair was still in pigtails, but they were now fuller and less childish-looking. Nichole's mind expanded as she raced away from 1st grade knowledge to 4th grade knowledge. She didn't notice anything unusual with her current family, except for Dad being a little harder on her dorky brother, Johnny. Of course, being closer in age meant that were able to fight on more equal terms, but Johnny was the one more likely to get in trouble.
Then the world came back into focus as Amy and Nichole finished their changes and adapted to the current reality. Nichole looked up at her favorite babysitter and said, "Mom and Dad said something about a day off, but I don't know what they were going to do."
Amy sighed and said, "So they mostly need an extra hand around the house?" She could understand that. Johnny and Nichole could be a handful, especially when they were bickering.
"I guess so. You'd think Johnny would be more helpful around, but he just avoids doing his chores," said Nichole. Of course, she weaseled out of her chores as often as she could, but she didn't need to tell Amy that.
"Well, I'm still getting paid, so I guess I'll stick around," said Amy.
"Ok, cool," said Nichole. She was reaching that age where she was starting to think she was too old to need a babysitter. But Amy was an exception since she was so cool. Amy had been looking after for as long as she could remember and she felt like family.
Nichole had no idea how true that was going to be. The Chronivac was starting with gradual changes, swapping the various ages of subjects around before it proceeded to its goal.