What Causes Recurring Stomach Cramping?

my daughter about every 2 months has a spell wher eshe wakes up in the morning crying because her stomach hurts and then spends hours throwing up. never running a fever of any kind. She stays this way most of the day refusing to eat and everytime she tries to sleep she is awakened with stomach cramps. Doctor wante me to monitor her diet but i have for several times now and can find no constant. what could be causing this and should be taken to a specialist? Is this something she will grow out of?