The Pope and Down syndrome

I am not a Catholic and know very little about Pope Benedict XVI, but came across the following while reading up about his visit to the US:

It may be worth noting that Joseph Ratzinger had personal experience of the Nazi approach to “rejects.” A cousin with Down’s Syndrome, who in 1941 was 14 years old, just a few months younger than Ratzinger himself, was taken away by the Nazi authorities for “therapy.” Not long afterwards, the family received word that he was dead, presumably one of the “undesirables” eliminated during that time.