[not2b]

But the second sentence is incorrect here! Sally has three siblings, one is her sister, so her brothers are not her only siblings. So ChatGPT correctly gets that Sally has one sister, but makes a mistake on the way.

[ricardobeat]

You meant four siblings? (3 brothers + 1 sister)

[sigmoid10]

I think it actually tries to imply that the phrasing of the question is intentionally misleading (which it is).