To whet your appetite and keep your writing fingers limber, take a good look at the photo, or let a prompt settle in your mind. Set a timer for a reasonable amount of time, be that five, fifteen, or thirty minutes. Then start writing.
Write about a family gathering that starts out well and ends badly. Or vice versa.
Write about family gatherings when you were a child. What did you like best about them? What were the most challenging parts?
Write an article with tips for making the holidays successful.