Lyric discussion by MayaMoo 

Cover art for Get Shaky lyrics by Ian Carey Project, The

To me, the song is about drugs and the word "brother" is used to represent this:

"Waiting for a trick from your brother" could suggest that the "trick" is the effect of drugs, and they're waiting for that to kick in, where they're in a europhic state as a result. I think the drug in this context is probably ecstasy. "Don`t be such a slave to your brother" could again show this, saying don't become hooked on the drugs, don't become a slave to them.

I don't think the song needs to be that deeply analysed though, it's just a bloody good song for a bloody good dance!