The mother of Christopher Reeve, the Superman actor, at first asked doctors to turn off his life-support machine after he was crippled in a riding accident.

Barbara Johnson, 76, who later changed her mind, spoke to The Sunday Times before the publication of an unauthorised biography, Somewhere in Heaven, by Christopher Andersen.

Reeve was thrown from his horse, Buck, during an eventing competition in Virginia. He landed on his head, shattered two vertebrae in his spine and fell into a coma.

Johnson felt that “the worst nightmare of my life” was unfolding before her: “Dr John Jane [chief surgeon at the Charlottesville hospital] told me that, if he did survive, Chris would be paralysed from the neck down and might not be able to breathe on his own. I knew my son wouldn’t want to live like that — he was a man of action, of adventure.

“I argued that Chris should be taken off life support. But the doctors and [his wife] Dana felt they should wait to see if Chris could express his own wishes.”

Nearly a week after his fall in 1995, Reeve regained consciousness. According to Andersen, Reeve also wanted the life-support systems turned off, but his mother now helped him to change his mind.

Reeve had a pioneering operation to reconnect his spinal column, which was relatively successful. Although he remained in a wheelchair until his death from heart failure, aged 52, four years ago, he recovered feeling in 70% of his body which, he boasted, allowed him to resume a full romantic life.

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