Decker and his brother Otto were born in Germany, but grew up in England.

After her brother Otto I came to power, an alliance and marriage was arranged with Hugh the Great in 936.

His brother Otto managed to escape Germany in July 1944.

He had encouraged his brother Otto to become a musician, but Otto committed suicide.

His brother Otto took up the government of Hoya.

He was succeeded by his brother Otto in the countship.

His brother Otto was given the area around Lemgo.

His older brother Otto also became a bishop.

His brother Otto died unexpectedly in 1911 and Al died in 1916.

After his father's death in 1910, Rupp's eldest brother Otto took over farming responsibilities.