My baby’s potty is different today ... he is on Similac advance. Some reddish color was there is this serious ?? Sometimes I cud see very small amount of blood in the stool where potty is normal or loose or tight. I am tensed

A. Anal fissures: These small tears are the most common cause of blood in baby's stool. They can occur when a baby passes a hard stool or if she has a more runny stool, which abrades the sensitive tissue that lines her anus. It's generally believed that a milk-only diet causes a more runny stool.