My DD began complaining of "tummy aches" pretty regularly at about that age, the ped said it was stress and I remember asking him what on earth a 3yo could be stressed about.
The stomach pains seemed to correlate to chores such as having to clean her room or other things she didn't want to do, so I assumed she was faking it at least half the time. Now she is 18 and suffering from anxiety, looking back with what I know now, I can honestly say I think the tummy aches were a legitimate symptom of anxiety and she just felt overly anxious about things she imagined would be unpleasant experiences...
