To be honest, I can't remember exactly what made me notice the number...I know my TF's and my, birthdays put together equal 9, but there were also a few other things that came up where the number 9 was the end result, or was a contributing factor, etc.....
And, of course, I haven't noticed it come up since - it seemed to just suddenly be a few things in quick succession that came up as 9's, so it made me take notice more than I normally would have, I guess.....