He was ordained a priest of the Roman Catholic religious institute of the Salesians of Don Bosco in November 1941.
In 1976, a few months into the Dictatorship, his brother Alfredo was assassinated in the Palottino Massacre.
Pope Francis recently launched the cause for Alfredo's beatification.
After his retirement, Leaden still lived in Buenos Aires, where he died a few days before his 101st birthday.
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