From what we've seen, the family tree's broken down something like this:

Aang (Last Airbender pre-Sozin's Comet/First Airbender post-Sozin's Comet) + Katara
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Tenzin the Elder ("Last" Airbender in the period between Aang's death and Jinora's birth) + Pema
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Jinora, Ikki, Meelo, Rohan (all airbenders) (each deciding to bear/sire multiple children)
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Descendants of the above four (Not as many wanting to go the multiple-child route, but at least encouraged to have at least one.)
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Shespa (Rohan's granddaughter) and others of her generation (Not all of them bearing/siring children, but still likely)
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| <- -possibly- a generation extra in here, but not likely. It all depends on when and how others got born.
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Tenzin the Younger, Gyatso the Younger, Nyima, Lhakpa, etc (the current young generation of airbenders).

Any of the descendants below Jinora/Ikki/Meelo/Rohan may not have been airbenders, depending on luck of the draw from Aang/Katara's genetics, or the bending status of their other parent. They're still considered part of the Air Commonwealth, but they don't all personally self-identify with the air nation or as Air Acolytes (see Bumi the Younger (nonbender) and Kya (waterbender), Tenzin the Elder's older siblings).

So, if Lhakpa ultimately doesn't want to technically be "An Air Nomad", there's plenty of counter-examples in place, though how much she'll feel like identifying with those groups is up in the air, as it were.

--- Philip

	Philip J. Moyer Contributing Writer, Editor and Artist (and Moderator) -- Eyrie Productions, Unlimited CEO of MTS, High Poobah Of Artwork, and High Priest Of the Church Of Aerianne -- Magnetic Terrapin Studios "Insert Pithy Comment Here"