L.R.
The other responses below are excellent. She is not too young to be dreaming and it's typical at this age for kids to wake frightened and have no idea why -- she won't remember the next day that she had a nightmare or even that she woke up. Get to her side as quickly as possible if you want her to return to sleep; having her "cry it out" only would make her feel she was being inexplicably punished at the same time she's truly frightened, and that's not a message you want to send her. I agree that being there but being very quiet with her (rubbing her back and reassuring her but not picking her up out of bed) is the best thing to do and she should get back to sleep fast. One thought for the future - She may have many changes in her sleep pattern over time. We all want our kids to "sleep through the night" and feel we've crossed a real hurdle when they do it as infants, but their sleep patterns can change many times over the years, affected by dreams, school worries, dietary changes, development of allergies, and much more. My child is eight and her sleep patterns still vary, including periods when she's wakeful and calling me at night because some worry has turned into bad dreams. It passes, in time. Enjoy your lovely daughter!