Donald's Nephews
Donald's Nephews (1938) is a Donald Duck animated cartoon which features Donald being visited by his three nephews, Huey, Dewey, and Louie. This cartoon is Huey, Dewey, and Louie's very first appearance in animation. The short, and the three nephews, was the idea of Al Taliaferro, the artist for the "Silly Symphonies" comic strip, which featured Donald Duck. The Walt Disney Productions Story Dept. on February 5, 1937, sent Taliaferro a memo recognizing him as the source of the idea for the planned short. Taliaferro subsequently introduced the nephews in his comic strip, which by this time had been renamed "Donald Duck", on Sunday, October 17, 1937, beating the theatrical release of "Donald's Nephews" by almost six months.
Duck family (Disney)
In the story "The Good Old Daze" by Tony Strobl, Grandpa Duck (an older Humperdink) appears in flashback taking care of little Donald along with Grandma. He's portrayed as a dedicated but rigorous grandfather. Grandpa's real name wasn't revealed in this story, but in an untitled one from 1951, where an old lover of Grandma called Humperdink has a cameo appearance. Don Rosa considered that this character became Donald's grandfather. In this same story, Grandma remembers an occasion where she and Humperdink heard one of her favorite songs. She says to herself, "I remember the band played that for Humperdink and me at the Fish Peddler's Picnic in 1905!". Besides, Grandma finds the ruined coat Humperdink had used to let her not step on a mud puddle and some romantic letters addressed to her written by Humperdink. Then she remembers some sweet names Humperdink used to refer to her in those letters.