When a friend sends text with "Go.to.the.dr" a Flock.com Ad shows up.
Asked her to retype the the message exactly the same and send again. It showed up again but it does not show up on her side. I have screenshots from both phones.
Welcome to Android Central! That's an odd one. Offhand, I'd say it's part of RCS, where the Messages app is showing you a website preview of what it thinks is a URL in your text message. But "Go.to.the.dr" wouldn't translate into any kind of URL that I'm aware of.
Looks like text speak for go to the doctor. Google it and that is what comes up. I see no connection to flock.com, although they are a team messenger and collaboration company. They also have an Android app. Does she have it installed on her phone?