Why does my 3 month olds poop have mucus in it&she poops 4-5 times a day but only a little bit? " shes been pooping like this for a week

Typically . Typically mucous in a baby's stool is due to mucous that was swallowed by the baby. However if the problem persists, your baby should be evaluated by her pediatrician. There are certain disorders of malabsorption that can result in this. The fact that it's of new onset and has only been for a week likely indicates the former. If you are concerned, please visit the doctor. Take care.