Thank you for the query.
means that your husbands small intestines is divided in some place (usually closely to the connection between large and small intestine). So the stools passes from stomach throughout the small intestine and gets excreted to the bag. Large intestine has no communication with the disconnected small intestine so the stool does not flows through it.
However, there is possible that from time to time something will be excreted through the anus. This is normal situation as large intestine gets cleared from the "old stool" and secrets mucus.
Hope this will help.