My son is now 19 mths and have been doing that since 6 mths. When he started I told the doctor and he said "lets talk about it when he's 1 yr old" - because then he can attibute it to having bad dreams. Which I didnt like.
He cries out like he is in pain. And he tosses and turns. And he is DEAD tired. Before my son was a year I would wake up and feed him milk with a lil cereal so he'd stay a lil full. But I stopped that when he turned one.
I would wake up at every sound because I was "used" to doing so until one day I was so tired, I just slept right through his crying and he went back to sleep. Who knew? She is going to start to expected it when she should start sleeping the whole night through.
Before I put him to bed I give him a warm bath. I burn lavender or vanilla oils. I give him a massage, read him a story and put on relaxing music, usually symphony with warm milk. But he still wakes up crying some nights. Maybe she is teething.... or gas or bad dreams might be contributing. I would give my son chamamile tea (more water though) and teething tablets or oragel and pat him back to sleep........