Philippe Bianchi admits he is becoming less optimistic about his son Jules recovering from injuries sustained at last year's Japanese Grand Prix and says the situation is putting the family through "daily torture".
Bianchi remains in a coma at a Nice hospital nine months after colliding with a recovery vehicle at Suzuka. The Frenchman, who drove for Marussia last year and was a part of Ferrari's young driver programme, suffered severe brain injuries in the crash and his family remain at his bedside.
"It's unbearable, it's a daily torture," Philippe Bianchi said in an interview with radio station France Info. "We sometimes feel like we're going crazy, because for me, it certainly is more terrible than if he had died. For we're not able to help him more than we can.
"Time goes by and I am now less optimistic than I may have been two or three months after the crash, when we could hope for a better evolution. At some point, you need to be well-grounded and realise how serious the situation is.
Phillippe says seeing his son wake up from the coma would lead to further difficulties as he remembers a conversation the pair had following Michael Schumacher's skiing accident in December 2013.
"If he finds himself with huge disabilities, we're pretty sure it's not at all what Jules would want. We had talked about it. He told us that if he were to have an accident similar to Michael Schumacher's, if he were even just not to be able to drive anymore, it would be very hard for him to accept it. Because it was his life."
Manor sporting director Graeme Lowdon has said the team would not exist without Bianchi, who recorded the team's first-ever points finish at the 2014 Monaco Grand Prix under the Marussia guise, after it returned to the grid this season following a spell in administration. At this year's Monte Carlo race the team created wristbands in his honour.