Question
My child was diagnosed with lactose intolerance. Dairy makes her sick but she can eat lactose-free dairy products without issue. Is there something else that should be explored, or is my child a rare one year old with true lactose intolerance?
Answer
It may be that your child had a viral intestinal infection that has left her temporarily lactose intolerant.
If she is otherwise growing well and has no abdominal pain, flatulence, or diarrhea when on a diet excluding only lactose then it's quite unlikely that something else is going on.
It may or may not help but will certainly not harm her to try adding a probiotic to her diet for a month or two and then trying lactose-containing foods again. Start with a small amount of lactose.
Check with your pediatrician if she continues to have these episodes of gastrointestinal distress.