One common theme is physical injury. For example, Kirk getting hurt during a mission and McCoy having to patch him up and offer emotional comfort. Another theme could be emotional distress, like Kirk dealing with the pressure of command and McCoy being there to support him.
Well, FanFiction.net could be a place to look. Just type in 'kirk mccoy hurt comfort' in the search. However, the quality can vary a lot. Another option is to ask in Star Trek fan groups on social media platforms like Facebook or Reddit. Fans in those groups are usually quite helpful and might be able to point you to some great works.
There are quite a few fanfics out there with such themes. One way to find them is to search on major fanfic platforms. Some might focus on how McCoy deals with Kirk's death in the context of some dark force or situation. However, it can be a bit of a hunt as there are so many Star Trek - related fanfics.
Well, in these fanfics, the concept of 'darkness' is often central to the plot. It can be used to heighten the drama and the sense of loss. When Kirk dies, the 'darkness' might spread among the crew, and McCoy might be the one most deeply affected. The 'darkness' could also symbolize the unknown future without Kirk. The reader character might enter this dark scenario and bring new perspectives. They could help McCoy come to terms with his grief and face the 'darkness' together, whether it's a literal dark entity or just the emotional void left by Kirk's death.
I'm not sure who Frank McCoy is specifically in this story as there is no more context. It could be a fictional character created for this particular story, or perhaps a name of a real person that the story is based on.
He may also develop a deeper understanding of Vulcan culture. Through taking care of baby Spock, he gets a first - hand look at the Vulcan way of life from an early stage. This could make him more empathetic towards Vulcans in general. For instance, he might start to appreciate their logic - based approach more.
Sandra McCoy might be an individual who has created or is associated with a collection of bedtime stories. Maybe she is a local storyteller whose bedtime stories have gained some popularity in a specific community. However, without further details, it's difficult to be more precise.