Socially Interactive Subtle Talented Equally Radiant Sweethearts or "S.I.S.T.E.R.S." is a band made by the former B.R.A.T.S.
While thinking of a new perspective of their future lives, the B.R.A.T.S. overheard Mercy singing and amazingly as well, which made the four girls thought of making a band. But, after a few days of hard thinking and a performance at Lyra Ubetcha Memorial School that led to them being banned by Benjamin Woolworth, they've decided to stand aside that dream and continue tormenting kids. However, after their redemption, the former B.R.A.T.S. go back to fully doing their dream and successfully became a band. In Part 1 of Lord Chaos Wars, "A Powering Start", while running from Chaos' army, they started weakening after noticing one of their weaknesses is music. Timmy and the gang noticed the S.I.S.T.E.R.S. were on a private stage preforming for their song and after finishing, Timmy ask if they could use their help keeping Chaos' army off their backs with the aid of their music equipment. In the ending sequence "A Fitting End", the S.I.S.T.E.R.S. performed in Fairy World celebrating Timmy for defeating Lord Chaos.