"I just wanna let you know,/How grateful I am to you./I appreciate all the hard work,/And kindness you put into,/Dear Spike!" -The Aquabats, ‘Dear Spike!’

All of the girls have at one point or another had Spike help them. However, it seems that the little dragon's good deeds often go unnoticed. So as an act of kindness, they all write letters to Spike.