Betette

"Thank you! Earthlings not all brain dead!"

- Betette

Betette, also known as simply Alien Child, is an Alien, being the daughter of Alph and the sister of Alphette and Gamette. She is named after the Greek letter "β," which is pronounced "beta."

Banjo-Tooie
In Banjo-Tooie, once Alph, Beti and Gammo reach the Icy Side of Hailfire Peaks in their UFO, Alph falls off the ship and dies. After being revived by Mumbo Jumbo, he asks for his three children, Alphette, Betette and Gamette, to be rescued, using his alien signal to make them appear.

Betette is found under an ice block near Alph. After being freed with the Bill Drill, Banjo finds her dead and suggests that Kazooie uses "beak-to-mouth resuscitation," but she quickly refuses, causing him to say that this is then "a job for a professionally qualified doctor," referring to Mumbo Jumbo, who needs to once again use a spell to revive her much like he did with Alph. After being revived, Betette says that "Earthlings not all braindead" and returns to Alph. Once the other Alien kids are all rescued, Alph departs with them from earth in their UFO and leaves a Jiggy behind.

Banjo-Kazooie: Nuts & Bolts
In Banjo-Kazooie: Nuts & Bolts, Betette and her family are vaguely mentioned in Banjoland by an Infopost in the description of the U.F.O. exhibit. It mentions how, in Banjo-Tooie, the ship carried the aliens.

Some aliens also appear frozen in cryogenic capsules in the Terrarium of Terror, although it is unspecified whether or not they are the same ones from Banjo-Tooie.