they would call each other in the olden days. In my family lines, often someone would have four, maybe even five or six, given names and not be called by any of them. Gran would call you what he thought you looked like to him.
The photo below is of Vinnie C Carpenter, his wife Flora Vandiver Carpenter, and their first-born, Tecumseh Carpenter. Vinnie was called Carp for obvious reasons. And Tecumseh was called “Cump.” This date of this photo is ca 1920. Cump Carpenter was born 1918.