Board Thread:Questions and Answers/@comment-28067574-20190904162421/@comment-39394247-20191003175006

TheHumanAmbassador wrote: ..Okay. I did more research. Turns out there is a biannual kind of flower. One that blossoms every two years instead of every year.

Maybe the golden flower is of that category, in which case, that means it could have taken a year PLUS a few months before Toriel left.

It still wouldn't be likely for the cyan human to fall within that time of Chara, but maybe it's greater than 5%? If so, Chara probably killed the cyan human in secret and gave the soul to Napstablook or someone else.