What Causes Frequent And Green Coloured Stools In An Infant?

Dear Doctors, Please help me. I have a baby of age 3 months and 10 days. Since more than a month her feces are greenish and she poos 6-7 times a day. We concerned doctor and she passed some exames, two drs said it could be normal but we think that it is not normal as we are feeling that our baby is getting weak. What could be the cause? Here are some information regarding. Age: 3 months 10 days height (at 3 months) : 60 cm weight (at 3 months) :4.9 kg She is feeding normal. rotavirus : negetative leukocytes in feces: positive reducing substances in feces: positive