Avinash:
Just an FYI, my sleep patterns have been dramatically altered since this entire life changing event began! Even today I sleep totally differently than before. Many evenings I go to bed at midnight or later and I'm up in a couple hours. I then may catch a nap after work, etc. There's no rhyme or reason to it and I feel rested. I rarely take any medication at this point (every now and then a pain pill but rare). I truly have great energy considering the brutality of the treatments, and I continue to improve every day. Speak to your father's doctors about it if he's not having any "Restful" sleep.
Best Wishes,
Steve