Also check to see if you have giardia, which turns the stool green and it floats. That's a pretty blunt way of putting it, but that's what it does. You can get it from your pets, too.
Hi
Welcome to the forum!
Stool can become green on taking food rich in green leafy vegetables. If this is not the cause, then the stool is passing out of the large intestine at a very rapid rate so the bile does not break down. It can also be due t a diet rich in refined sugar. A viral infection can change the stool color to dark bottle green color. You can get a stool test done.
Since there is blood which you can see, it is coming from the lower gut. This can happen in hemorrhoids, rectal polyps, diverticulosis (outpouchings from the bowel wall), inflammatory bowel disease, or dysentery.
In hemorrhoids the blood falls after the stool. In fissures it lines the stools. In all other problems the blood is mixed with stools.
Since your mother has diverticulosis, this should be the primary cause investigated. Please consult a gastroenterologist. Maybe your mother’s GI doctor can help you too.
It is difficult to comment beyond this at this stage. Please let me know if there is any thing else and do keep me posted. Take care!