Georg, 94, told the Neue Post that his brother was mentally fit but that he tires easily.
“The greatest fear is that the paralysis could at some point spread to his heart. Then it could be over quickly,” said Ratzinger, adding he prayed every day for a “good” death for himself and his brother.
He also said the brothers spoke every day on the telephone. “That is a great gift. In this way, no-one is alone.”
“I very much hope that I can travel one more time to Rome to celebrate the 91st birthday of my brother on April 16. But that is a long time away, who knows what will have happened by then,” Ratzinger was quoted as saying.
Since resigning, Benedict, a conservative whose seven-year papacy was marked by mismanagement and financial scandals, has been living in a former convent in the Vatican gardens.
He makes only rare public appearances.
The Vatican had no immediate comment but a source close to the former pope said Benedict was continuing to receive visitors, including some just last week.
Georg Ratzinger led one of Germany’s most famous Roman Catholic choir schools, the Regensburger Domspatzen, or Regensburg Cathedral Sparrows, from 1964 to 1994.
Last year, an independent report found that more than 500 pupils there had been subjected to physical or sexual abuse between 1945 and 2015. Ratzinger has acknowledged that he had slapped pupils in the face but said he had not realized how brutal the school’s discipline was.
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