It's: siblings :)

In some episodes of Animaniacs, the characters used "Sibs" (short for "siblings") in this context. It certainly isn't common, although I liked it very much and would have used it had I had any siblings. We usually address our siblings in the Philippines in special ways if the sister is older we must say "ate" for showing respect and for older brother we must say"kuya" except in England or USA In England, they tend to just say a greeting, and not really specify who it is to. If you want to add something, you could add 'guys' Hey guys, Hi guys etc.

Siblings.