Based on the described scenario, it is most likely that Kaylee is suffering from specific phobia.
This refers to the fear of something that is sometimes irrational and causes weird behavior and is diagnosed to be a psychological problem.
Hence, we can see that based on the fact that Kaylee is scared of snakes and as a result, avoids outdoor activities, and does not even spend time alone in the backyard, she likely suffers from a specific phobia.
Read more about phobias here:
https://brainly.com/question/738362
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