I do get your sentiment, but you could have picked some better examples:

> Could be an only child

In which case, odds are that they're also the first child ;)

> or the spouse is stay-at-home

Which is a full-time job in itself

> or the author has family wealth and doesn't need a full time job.

which is far far less likely than the assumption you're rebuttelling

could also be the first child ;)

or literally none of those options

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