"Her parents have a restaurant."
Translation:Hennes föräldrar har en restaurang.
The only hint I can see on "parents" in the incubator is föräldrar. You should see this one too.
If you see the hint föräldrars here, it is because of a bug concerning hints on words with an apostrophe in them, which makes the hint for parents' be shown on words without the apostrophe. Duo is working on it, but until they fix it, be careful when hints give you words ending in an s.