E.D.
My son is 2, and also having some nightmares, waking up scared. It's normal at this age. I've also noticed he has fears during the day (loud noises, strangers, etc). Just a developmental thing, becoming aware of the world. Does your daughter have a night light in her room? If not, I recommend getting one. Also, we leave our boys' bedroom door slightly open, and for a long while left the hall light on for them. When my son wakes at night, I or my husband will go to him, comfort him, get him water, give hugs, kisses. Then we tell him, "it's okay now, go back to sleep." This is usually enough. Don't feel like you need to bring your daughter to bed with you, that will most likely become a bad habit. Just comfort her, and leave, go back as need be. Just letting her know you are there will be a big comfort. Good luck!