You write well. Strong prose, no clumsy passages, no unintentional howlers. And your descriptions are vivid and well presented.in fact, I'd say that your writing is good enough that you almost get away with the fact that you haven't told us a story.
Almost.
What you have here is an anecdote, a narrative concerned solely with surface events with no deeper meaning or implications to be drawn from them. Anecdotes are what you share with friends, usually prefaced with something along he lines of, "You won't believe what happened to me today." There's nothing wrong with anecdotes, and often they are not without interest, but they are simply an account of something that happened. In this case, that something is: Sara falls asleep in a storm, has a frightening dream, and is awakened by her father, who calms her down.
My question is one your readers will ask, and it's the fundamental question you should first ask yourself of anything you write: So what?
This is not meant to be a snarky put-down. It gets to the heart of what will keep your readers coming back. So what would turn this anecdote into a story? In the broadest sense, it's change. A character (or characters) begins at Point A and progresses through a sequence of obstacles, either compelled by circumstances or personal needs and desires, until they arrive at Point B. The crucial element is that Point A and Point B are not the same place. Whether there has been a change in circumstances, or in your character's perspective and attitude, the process of change taking place is the story part. And it provides the reader with that "What's gonna happen next?" Impulse that will keep them turning the pages to find out.
In truth, you have an innate sense that this is a requirement. You've front-loaded your narrative with a host of elements that will make the reader want to know what's going to happen next. It's only when they reach the end and discover that the answer is "Not much," that they will feel disappointed. Shouldn't do that to your readers.
So what's the "something" that needs to happen? Ya got me. It's not my story. The possibilities, however, are endless. Think about what might represent a disruption in the status quo? You provided one hint at the beginning when you mention that Sara's father didn't like it when "she was scared of a little storm." But then, when we encounter him, turns out he's everyone's idea of a great dad. Good for him. And good for Sara. I love it when children have loving family environments in which they feel nurtured and protected. In the real world, that is. In fiction, they are death. Good people who get along and enjoy life seldom have stories gathering around them. It's the warts, scars, bad decisions and unpleasant character traits that cause problems, and in fiction, problems and how we deal with them are the coin of the realm. So what problems might Sara encounter if her father was less an example of the perfect dad?
Of course, you could always take a page from the idiot savant of storytelling, Stephen King, and make the cat real. That would open some new doors for you.
With writing as strong as your, and a set-up as promising as this one, you owe it to yourself, and your readers to make it count.