I think Robert Fulgham wrote an essay about singing to children. He tells about how he visits a Kindergarten and asks the kids to raise their hands if they can sing. All do. He goes to a high school and asks the same question. Very few hands. Do children lose the ability to sing somewhere between age 5 and 15? 'Course not. They are not encouraged to sing and they think that they have to have perfect pitch to be able to sing. Wish I could quote chapter and verse, but it was one of his collections of essays.