Tom's sister came over on Saturday with all her offspring.

Quel mot ou expression interprète le mot « offspring »

dans le sens de

[humorous or formal] a person's children:

Tom's sister came over on Saturday with all her offspring.

https://dictionary.cambridge.org/dictionary/english/offspring

Petits, progéniture, rejetons,...?

EDIT (merci @Luke Sawczak)

To clarify the connotations for non-Anglophone answerers and help search for equivalents: the word is normally associated with zoology, hence the humorous side is by comparison with "her young" or "her whelps" or "her issue"; on the other hand, it also appears in traditional translations of the Bible, e.g. in promises that Abraham's "offspring" (nowadays "descendants") will be numerous. In the example given, of course, the formality is misplaced and so also humorous :)