Hey, welcome to the site! From what I understand both from this site and other websites a stomach bug is not airborn except while the person is actually being ill. So if you were there while she was being sick then yes you could have gotten it. Also if people don't use proper hygeine after using the restroom and then handle food or soemthing you touch and then if you didn't wash your hands. Basically if you wash your hands thoroughly before putting them in or near your eyes, nose or mouth or on anything going in your mouth and you weren't there when she was ill than you should be fine. Hope this helps!
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