Della Duck

Della Duck is the mother of Huey, Dewey, and Louie, and twin sister of Donald.

She is voiced by Paget Brewster.

Appearance
Just like how Donald mostly wears a sailor shirt, Della was typically sporting a pilot's outfit.

Background
Prior to the events of the series, she used to go adventuring with her brother and uncle.

Days before her sons hatched, Della – a passionate pilot and aspiring astronaut – took off with a spaceship built by Scrooge: The Spear of Selene. When she got caught in a cosmic storm, Scrooge tried to guide her through it, but contact with The Spear was lost, and Della hasn't been heard from since. Donald, blaming Scrooge for Della's disappearance, cut off all contact with his uncle and raised the triplets by himself, while Scrooge spent years trying to find his niece, until his board of directors cut the expenses.

Season One
Thus, she only appears on photos and paintings throughout most of the first season, making her first major appearance within the franchise in a series of flashback stories in issue #2 and #3 of the DuckTales comic book.

In the season one finale, she is shown to be alive and well on the Moon, unable to contact Earth.

Trivia

 * Her character had previously appeared in Disney comics, this is her first appearance in any animated media.