Also, there is so much we can do as health care team/physical therapist and you as a family (talk to your physical therapist and discuss that with him, he should know).
Coma following a
stroke could happen, especially if a specific area of the bran, the reticular formation, is affected. So until the brain decides that your nephew is safe, he would wake up. Just wait and have faith, it is gonna be a long journey.
I will keep praying for him..