I'm upset and need answers reguarding standard procedures for stroke victims.?

My mother suffered a stroke about 3 weeks ago. It happened at home and she was taken into the ER. She was out of it for awhile when she was there. The next day, she suddenly snapped out of it and was normal again. The doctor told my bros that my mom was a good candidate for a new operation(putting tubes in her injecting medicine that would help her arteries open up) that would help her. He told them however, that theres a 10% chance that it could cause a hemmorage. My bros decided not to go thru w/the op because my mom seemed ok and the tests according to the dr didn't indicate any needed immediate medical attention. So the next day, she suffers another stroke at the hospital and this time it messed her up bad. She was basically in a coma, unable to move or speak. This time my other bro ok'd the op and it stabilized her. Thank God this time another stroke didn't occur. She can speak but I can only understand 30% of what she's sayin and her right side is paralyzed. She's slowly recovering but I'm wonderin if there was something the hospital didn't do that could've prevented the 2nd stroke. A note: I wasn't there at the hospital during her 1rst or 2nd stroke and I'm still too upset to speak w/the dr. in charge at that time. But according to my bros who were there, the dr. didn't seem too helpful in enlightening them with what strokes were and didn't stress the importance of the operation. We're not even sure if there was even a test done after the 1rst stroke and even if there was it didn't prove a thing because my mom still suffered a 2nd stroke AT the hospital the next day. Any knowledge or advice is greatly appreciated.