I started learning guitar when I was 20, and I went all the way with it.
So I don't think you absolutely have to start early in childhood, to be able to
get far.I think it's more like if you have music in you, then you'll have been
tapping on the furniture and singing and such all along (and that stuff counts
as practice. For example, my years of banging all over dashboards and the
arms of chairs, "drumming" to music I'd hear, translated very well onto an
actual drumset when I finally got one. It was as if I'd been playing all along.