Gallstones don't pass on their own...they are not like kidney stones! I had my gall bladder removed in December. Gallstones can block the bilary duct and cause bile to back up to the liver which can cause jaundice (yellowing of the eyes and skin), which is an emergency situation. Additionally gallstones can travel farther down from the gall bladder to the cystic artery (where the digestive juices from the pancreas and the digestive juices from the gall bladder meet, which can cause pancreatitis and this is also a emergency situation.
My surgeon told me that if I had another gall bladder attack to go to the ER and that I would be admitted but it could take up to a week for an on call surgeon to perform the surgery. So unless the gall bladder attack involves one more gallstones blocking the bile duct or cystic artery, it is not emergency situation and doesn't require immediate surgery.
I still take that it is important for your sister to consider scheduling surgery for gall bladder removal as the chances of one of the more serious complications occuring with the next attack are high especially if there are multiple stones present in the gallbladder.
Gallstones don't ever pass out of the body. Once gallstones have formed, more stones are destined to come. There is a medication that dissolves stones comprised of one type of substance; however, the stones in the gall bladder are using a mixed bag in terms of what they are comprised of. Additionally, it takes up to 2 years for the medication to dissolve the stones and in the meantime the med makes many people sick. Also, in 90% of cases, the stones reformed after they were dissolved by the medication. Not worth going that route in my opinion.
Your sister can change her eating habits to try to prolong another gall bladder attack by excluding all diary, fatty meats (only meat without skin is okay and no red meat), vegatable oil (olive oil, omega 3s from fish are okay), and highly processed foods.
Wishing you and your sister the best. Take care.
femmy
Perhaps the doctor is waiting to see if the gall stone will pass on its own. Sometimes they do that with kidney stones too.
Hang in there.
mkh9