Yeah, as you say, it is learning without realising it. Our eldest Aisling's Japanese skills really picked up after her grandmother, a kindergarten teacher, visited us from Japan and introduced her to games and rhymes in Japanese.
In a way, as music and song were my reason for starting Irish, I have benefited from the songs I learned (and every now and then a useful phrase pops up that I have heard in a song and therefore remembered more easily.)
One important feature of the technique, I think, is that exposure to the sound systems of a particular language at an early age encourages the brain to retain the circuitry for recognising those patterns (which would otherwise be removed for biological economy) for use later in life. It's one reason why people who come back to a language they heard as a child often have an easier time than those who have never heard the sounds before.
Futa Fata is a great site, Saoirse. I hope you'll add it to our useful links section. (The phpBB version of our site is running stably and securely, so I don't think we'll have to move again for the foreseeable future - touch wood, of course.
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