Bowser

It took awhile but I finally figured what Abby means by the "Bowser song."  It's a song by the Florida Georgia Line called This is For my People Back Home.  There's a line that says "we're always thinking about you," however Abby sings it "we're always thinking of Bowser."  I've tried to suggest the correct version, but of course Abby doesn't want to hear it :)  Mystery solved, point Mommy!