Origin of moms/pops/fams

I realize that the none of the words “moms,” “pops,” and “fams” is a plural construction. But how long have they been in use, and what is the derivation of putting an “s” at the end?

“Moms”, “pops” and “fams” are all plural constructions using the standard (and very old) “s”-plural common to most English nouns.

Do you mean, why is that construction sometimes used as an affectionate sort of diminutive when addressing a single individual, such as “Hiya pops, how ya doing?”

If so, Wiktionary sez it’s a shortened form of the diminutive suffix -sy. “Momsie”, “tootsie”, etc.

In slang usage, someone will refer to “my moms” or “my pops,” and it’s obvious they’re referring to a single person. Pretty sure “fams” works the same way. So “fams” just got done up the way “moms” and “pops” were to make a consistent practice? Sound legit.

Unless the person actually has two moms.