Ghost messages (no sender, no content)

My wife got an new iPhone 6s a few months ago. Ever since, about once or twice daily, she gets messages that pop up and the end of her messages folder. She receives no notification, there is no sender info, or content in the message either. You wouldn't know they were there unless you scroll to the bottom and see them all just hanging out. They don't do anything malicious, just are annoying. I've searched google and apple.com for answers, but can't seem to find anyone that has had the same issue.

I recently got an iPhone 6s+ and have never had the issue. She just deleted about 100 messages, or I would post a picture. As soon as more show up, I'll screen shot it and post it. But if anyone has experienced the same thing, please let me know.

This is in the text folder, and has nothing to do with mail, gmail, or any other app. Just texts.

Thanks!