Forgot to Tag a Person Pop Up

Some of our users keep forgetting to tag a person in a new update so the comment goes unnoticed until you happen to see it. Would be good to get a pop up or not be allowed to make an Update/Comment without tagging someone. I think it's also the set up of the UI with the box below the comment box to add names in. If it was above, similar to email then maybe that would trigger them to add in the people they want to send their message to.