The Legend of Korra

I assumed they were all airbenders, since Pema asked Katara if Tenzin and his siblings were as hard to raise as her current 3 airbender kids. She mentions the other two (Kaia and Bumi?) were quite a handful, but Tenzin was always more serious... I don't recall any mention of what kind of benders they were. O.o;

Just because Tenzin is the only airbending master doesn't necessarily mean his siblings aren't airbenders as well--not all benders are masters, after all.

But I'm certain we'll meet them as the series progresses, so we'll find out for sure!