My 16 year ld granddaughter s sched gor gall bladder test that injects something to intentionally stimulates all bladder because se s having any symptoms f gb trouble. I and her mother have already ad gb removed. My question s that the last week, her stools are black. Her mother had black stools too. What causes this because I thought gb trouble was supposed to cause clay colored stools. Please answer
Thank you.

The bile salts can cause the stool to turn black. The gray usually denotes a lack of bile. So, depending on reason for the gallbladder removal, this can be perfectly normal.

As always follow up with a professional medical doctor is always recommended.