Trust your sister.
She has been caring for him day to day and probably now hour to hour. She has learned a lot I am sure and understands how to care for him. Let her see him through.
Just my 2 cents.
Prayers for you and your father at this time.
What you is true. But my sister is having the hard time accepting it and keeps looking for a miracle and just cannot let go. This is kind of what is making it hard.
She lives at the hospital and I fear it is taking a toll on her. I live about 50 miles away but I am caring for a 90 year old Aunt and I am already stretched.