A childhood belief about farting

As a child, I was at first very puzzled on learning that one's body contains "organs'. Why do we never hear music from those organs, I thought? One day I was playing cards with two girls from the neighborhood I then lived in, Kelly and Olivia. I decided to share with them my perplexment about organs in the body. They laughed and I didn't know what to make of it, whether they understood what I was talking about, and just what they were laughing at. Later, while we were still playing cards, Olivia farted, and Kelly said, "There -- there's some music from one of Olivia's organs!" Then there was more laughter. I didn't know enough at the time to know what level of understanding that meant Kelly had of the question I had posed, or if she know what bodily "organs" actually are. But today I see she must have had at least some understanding of my question. But was the laughter at that point because kids find farts funny, or becauase Kelly (and maybe Olivia too) understood the difference between bodily organs and the musical instrument of the same name, and maybe found it funny that I didn't know the difference? I guess I'll never know for sure, or whether they were lauging "with me" or "at me".