The name "Sam (Samuel/Samantha)" primarily serves the function of Infantilization. It acts as a linguistic bridge, reducing social distance and creating a sense of intimacy between the speaker and the bearer.
Morphologically, "Sam (Samuel/Samantha)" exhibits Reduplication. This formation typically involves adding a softening suffix, making the name easier to pronounce and more pleasing to the ear.
Tracing its roots, this form likely evolved from Victorian Nursery Talk traditions. Historically, such diminutives were often used to distinguish younger family members or to show affection within formal households.
In terms of sociopragmatics, "Sam (Samuel/Samantha)" is most appropriate for Family Only. Using this name implies a specific level of trust and can sometimes function as a secret code.
Contemporary usage sees "Sam (Samuel/Samantha)" undergoing Gender-Neutral Evolution. It is moving beyond its traditional boundaries, finding new life in social media handles.