and-his-mother

Phrase

(idiomatic) Serves as an intensifier for an inclusive noun or phrase such as everyone, anyone, each someone or all someones.
It looks like everyone and his mother has come out tonight.
Anyone and his mother could see through that disguise.

Usage notes

Being idiomatic, the phrase can take a number of forms. Versions that replace his with their are common, and in this case mother can be in the singular or plural. and her mother is also attested, used when emphasising that a group is mostly or entirely female. Regional and dialectal synonyms for mother such as mom, mum, mam, momma, mama and ma are also commonly substituted.