I would guess that you are having a font cache problem and that InDesign is holding on to an earlier version that didn’t have the apostrophe.

Thanks Mark,

I’ve tried that font cache cleaner program that is recommended, didn’t seem to help. Besides, other changes I’m making are showing up, that’s the only reason I don’t thing it’s the cache. Or is it selectively ‘cache’ing?

Do you have smart quotes turned one? Does your font not include a “dumb” apostrophe in it as well?