Billy names his two coon hounds "Old Dan" and "Little Ann". 

As Billy makes the long journey home with his two pups, he goes over a whole list of names in his mind, trying to find just the right ones.  For the boy, he considers "Red", "Bugle", and "Lead", and for the girl, "Susie", "Mabel", "Queen".  None of the names seem to fit.  Then suddenly, as he is resting awhile at a spot near the river,  he notices

"...carved in the white bark of a sycamore tree...a large heart.  In the center of the heart (are) two names, 'Dan' and 'Ann'.  The name Dan (is) a little larger than Ann.  It (is) wide and bold.  The scar (stands) out more.  The name Ann (is) small, neat, and even".

Billy looks at his pups, the boy outgoing and brave, the girl smart but more reticent.  The names are perfect, and Billy christens his pups "Old Dan" and "Little Ann" (Chapter 6).

Billy's pups are his pride and joy.  Starting when he was eleven years old with only twenty-three cents, he had begun saving to buy them, painstakingly putting aside the pennies, nickels, and dimes he earned in a tin can hidden in the loft in the barn.  For two long years he had spent any free time he had in the summers catching crawfish and minnows and selling them, along with vegetables and corn, to the local fisherman, and gathering berries for which his Grandfather gave him ten cents a bucket to sell in his store.  In the winters he trapped with "the three little traps (he) owned", and his Grandfather sold the hides to the fur traders who came by the store.  Finally, when he is thirteen, Billy has enough money, fifty dollars, saved in his can.  He brings his savings proudly to his Grandfather, who has promised to order the dogs for him (Chapter 3).