User blog comment:PhineasxIsabella/Phineas and Ferb Trivia/@comment-2217944-20100730194504

I know. What I'm saying is they had 5 songs in their debut appearance, 1 song in "Thaddeus and Thor", 1 song in "Just Passing Through", and the 2 songs in SBTY.

5+1+1+2=9 songs.

If you disregard the ones sung by the individual members, that's still 6 songs by the entire band.