<s>[INST] My 3 year old has been complaining of back pain for the past 3 weeks. We have had her urine tested and blood work has come back normal. We were told it could be that she s constipated even though she poops 2-3 times a day. We started giving her miralax 3 days ago and she started drinking Pediasure with fiber. Is this all I can do at this point? How long before we might start seeing a change? [/INST] Hello,Did your child have any history of trauma? If yes get an mri spine done.Otherwise usg abdomen for evaluation of other abdominal pathologies. </s>