My grandmother (born 1902) was a pianist of great talent and skill. She required both her daughters and all her grandchildren to sing, and she would tolerate our efforts to learn to play instruments that were not the piano.

When she got bored at parties, which was frequently, she would sit down at the piano (there was always a piano in those days) and start to play show tunes -- and not simple ones, either. Noel Coward, Jerome Kern, the Gershwins and Cole Porter were her favourites, and I remember leaning over her shoulder to turn pages and singing "Love For Sale" at an unsuitably early age. At a certain point she would summon somebody to the piano and strike up what she considered that person's party piece, not necessarily what that person particularly wanted to sing at that moment but what the hey, she was a force of Nature.

At Christmas, there was always at least an hour but often more of working through the Oxford Book of Carols, especially the more recherche items.

The net effect of this practice was that I have always been able to stand up and perform without qualm. I know about stage fright, but I have never experienced it; disappointing Grandma was a bad idea, so I learned to pin my ears back and sing.

On the whole, very valuable training.