Well, it depends on the fandom community. There are many fanfics out there, and while there could be one about Mary Crawley being pregnant, it might not be that easy to come across. Some fanfic authors might be interested in exploring such a storyline for Mary Crawley, but it's not guaranteed to exist in a widespread or easily found form. You'd really have to dig into the relevant fanfic archives and communities to know for sure.
Cora could be many things. She might be the protagonist, driving the story forward with her actions and decisions. Or she could be a side character that adds depth to the plot, like a confidante to the main character.
The plot could involve Mary Crawley's pregnancy being a surprise to those around her. There could be drama as she decides who to tell first, like her family or her husband. And then there could be a series of events related to her preparing for the baby, such as dealing with the arrangements in the house, and the reactions of the servants. Also, there might be some conflict with other characters who have different opinions on how she should handle the pregnancy.
Well, it could be that Cora was a kind-hearted fairy. Once upon a time, she decided to help a poor family in a human village. She used her fairy powers to make their crops grow and their sick child get well.
Once upon a time, there was a little rabbit named Benny. Benny lived in a beautiful meadow filled with colorful flowers and tall green grass. One day, Benny decided to explore the forest beyond the meadow. As he hopped along, he met a wise old owl sitting on a branch. The owl told Benny about a magical waterfall deep in the forest that could grant wishes. Benny was very excited and set off to find the waterfall. After a long journey, he finally found it. He closed his eyes and made a wish for all the animals in the forest to live in harmony. And from that day on, the forest was a peaceful and happy place.
Hard to say. Sometimes stories like Cora Miracle take inspiration from real life but are embellished or changed to make a more compelling narrative. Without more specific information, it's difficult to determine if it's entirely true.