I think this is mostly harmless.
To use your medicine example, it'd be more like looking up a webMD article for the common cold and seeing one about the common cold in martians. Don't we as readers and observers to think critically about what's presented to us? This reminds me of people who take outlandish and impossible Onion article headlines, don't bother reading the story, and then share it with shock and indignation on social media.
Also, in the example of your niece, this would serve as a good learning point for her then. If someone is confused by this, I'd say it's harmless confusion and it's something that's safe to be confused about.