Only about 40% of the 1956 recording was actually live.
He was just 3 years old at the time of the recording.
He has said how this was the most difficult part of the recording.
In 1933, she made the first of her many recordings.
At the same time, he also made some more of his own recordings.
Most of the show's recordings were lost in a 1978 fire.
He made a number of recordings in the 1930s and 1940s.
Since then they have made a very large number of recordings.
And there were others in the early period of recording.
Many of the recordings had not been heard since the 1970s.