Thank you for your query.
Do not panic
This maybe a case of lactose intolerance
If the weight of the baby is increasing ,normally and she is feeding well there is no reason to worry.
If the occult blood remains positive then there is microscopic bleeds in the stool.
You need to change the milk to soy based milk and avoid fruit juices and wheat as well.
Give her some probiotic
drink and lots of yogurt.Repeat the stool test
after 10 days.Hope this answers your query.Wishing your child a speedy recovery.Have a nice day.