Audiobook: Grandpa's Darlings

Fiction, or fact? The narrator asserts it's fact.
The narrator is an author, whom her little nieces call "Auntie Belle". There's also an "Auntie Dule" (proper name Julia), Grandpa and Grandma, Mama and Papa, and eventually an Uncle Ross (Isabella Alden's husband, Gustavus Rossenberg Alden). The book is made up of vignettes of the funny sayings or doings of little Minnie and little Gracie, and how these lead to Grandpa's wise lessons for both the little ones and the adults. - Summary by TriciaG